Neito Monoma / Phantom Thief

Name: Neito Monoma

Gender: Male

Hero Name: Phantom Thief

Affiliation: U.A. High School, Hero Course, Class 1-B, Student No. 18

Former School: Aizoe Junior High School

Birthday: May 13

Height: 170 cm

Blood Type: A

Birthplace: Kanagawa Prefecture, Japan

Favorite Things: French cuisine, bandes dessinées (French-language comics)

Personality Keywords: Sarcastic, prideful, neurotic, persistent, kind to his own “in-group”

Voice Actor (Anime): Kohei Amasaki

Monoma is a Class 1-B student whose Quirk allows him to copy others’ Quirks for a limited time.

He compensates for the inherent limitations of his ability with high situational awareness, bluffing, and psychological warfare.

He is infamous for his obsessive rivalry with Class 1-A and his relentless, cutting sarcasm.

Despite this, his classmates in Class 1-B recognize his strategic mind and see him as one of their key tacticians.

Monoma has sleepy-looking eyes, a nihility-tinged smile, and blond hair that reinforces his “handsome but shady” vibe.

At first glance, he seems lazy and unmotivated, but in reality he is highly strung, fastidious, and fiercely proud.

His pride is so intense that when his emotions spike, he breaks into a hysterical, high-pitched laugh and fires off a stream of barbed remarks.

This “villain-flavored” behavior often makes him look more like an antagonist than a hero candidate.

He is outwardly cynical, mean-spirited, and constantly mocking, especially toward Class 1-A.

However, he is loyal and surprisingly gentle toward his own “in-group,” especially his Class 1-B comrades.

Monoma tends to impose his own private rules for judging victory and defeat.

Even if he loses, he will challenge the same opponent again and again until he personally feels satisfied, which makes him extremely persistent and annoying to deal with.

He is often seen together with Itsuka Kendo, who acts as his handler and “brake.”

Their running gag is:

1) Monoma mouths off at Class 1-A,

2) Kendo chops him in the head with a hand strike,

3) Monoma collapses.

Although he projects himself as a genius and a strategic mastermind, his actual results can be inconsistent.

He was the only Class 1-B student to fail a subject in the first semester final exams, earning a make-up session.

Despite this, he shamelessly mocked Class 1-A for having five students in remedial classes during training camp.

His ability to forget his own shortcomings while attacking others shows just how strong his mental “armor” is.

Underneath his antagonistic behavior lies a complicated complex about his own Quirk and hero ideals.

He was repeatedly told as a child that his Quirk could never make him a “superhero,” only a side character.

He described this to Hitoshi Shinso as the feeling of early dreams and hopes slowly becoming a burden.

Like Shinso, whose Quirk is often labeled “villainous,” Monoma faces the paradox of having to act un-heroically in combat despite wanting to be a hero.

Over time, this contradiction and the external judgment hardened into his twisted, bitter persona.

Even so, he shows clear empathy and moral sense in crises, such as when he protects Eri from violent civilians during the evacuation period at U.A.

His rivalry with Class 1-A is partly genuine resentment and partly a warped kind of trust and expectation.

He wants Class 1-A to be worthy opponents, and in later arcs he even cries out in despair when Katsuki Bakugo is gravely injured in battle.

Monoma harbors a burning competitive spirit toward Class 1-A as a whole.

Since the U.S.J. incident, Class 1-A has gotten most of the attention, and Monoma is determined to prove Class 1-B is just as capable—or better.

He constantly looks for opportunities to provoke or upstage Class 1-A during the U.A. Sports Festival, the Cultural Festival, and joint training.

He particularly fixates on Katsuki Bakugo, whose explosive temperament mirrors Monoma’s own twisted pride, suggesting a form of hostile kinship.

With Class 1-B, Monoma functions as one of the organizers and “idea men.”

His classmates rely on his tactics and his ability to coordinate Quirks, even if they often have to endure his snarky commentary.

Teacher Sekijiro Kan (Vlad King) recognizes Monoma’s frustration about being told he cannot be a “main hero.”

During the second war against the villains, Vlad King firmly tells him that he has always been, and will continue to be, a main character in his own story.

Mirio Togata, despite hardly knowing him at first, quickly sees through Monoma’s feelings of inferiority and antagonism.

Eri jokingly refers to Monoma as “the negative side of U.A.,” underlining how visibly he embodies the darker edges of U.A.’s intense competition.

Monoma’s hero costume evokes a tuxedo layered with a black jacket, giving him a theatrical, gentleman-thief aesthetic.

This design matches his hero name “Phantom Thief” and his showy, stage-like approach to battle and taunting.

His costume does not include directional or power-enhancing devices, as his Quirk activates simply through touch.

Instead, his key support items are three watches attached to his belt.

These watches are used to track the duration of the Quirks he has copied.

They also act as a deliberate bluff: enemies are meant to mistakenly assume he can hold only three Quirks at once.

Because his strength lies more in timing, coordination, and deception than in raw physical enhancement, his costume is relatively simple.

The emphasis is on psychological impact and information games rather than brute force.

Quirk Name: Copy

Monoma’s Quirk allows him to copy the essential nature of another person’s Quirk by touching them.

Once copied, he can use that Quirk for five minutes.

Within that five-minute window, he can store multiple Quirks at once.

The notable limitation is that he can only *activate* one Quirk at a time.

Because he can swap Quirks rapidly, he can pseudo-combine them through smart timing.

For example, he can use a defensive Quirk for an instant, then immediately switch to an offensive Quirk in the next moment, creating a combo-like effect without technically using two Quirks simultaneously.

He can stock up to four Quirks at once.

However, there is no canon indication that four is his absolute upper limit or that the three belt timers represent a real cap, especially since he himself states they are a bluff.

The true power of Copy lies in teamwork and pre-planning rather than solo power.

He shines when surrounded by allies with varied Quirks whose abilities he understands in detail.

Limitations and “Duds”

Monoma must understand the basic nature and usage conditions of a Quirk to use it effectively.

Simply copying an unfamiliar Quirk is often not enough to employ it well in the heat of battle.

Even when he understands a Quirk conceptually, the original user has usually trained with it for years.

So in terms of raw mastery and fine control, Monoma almost never surpasses the Quirk’s original owner.

He refers to certain copied Quirks as “duds,” where the Quirk’s *conditions* or *stored resources* are missing.

In those cases, he technically copies the Quirk, but nothing meaningful happens when he tries to activate it.

For example, copying Taishiro Toyomitsu’s (Fat Gum’s) “Fat Absorption” fails if Monoma’s body lacks the necessary fat stores.

He can access the Quirk’s nature, but without the material resource, it’s nearly equivalent to having no Quirk at all.

Similarly, copying Momo Yaoyorozu’s creation-type Quirk would likely be near-useless if he lacks both sufficient body fat and the complex structural knowledge required.

He might technically trigger the Quirk, but producing anything practical would be extremely difficult.

The clearest example is Izuku Midoriya’s One For All.

Monoma can copy the *concept* of “stockpiling and passing on power,” but not the gigantic reserves of power accumulated by the previous users.

Because of this, he does not suffer the dangerous recoil that Izuku experiences when unleashing high output.

He himself never realizes how close he came to risk, because the copied version lacks the gathered strength that makes One For All so volatile.

Monoma also tries to copy Eri’s Rewind at the request of Shota Aizawa, who wonders if that could help teach Eri to control her Quirk.

The copy is another “dud”: Monoma can manifest visible signs like growing a horn, but he cannot meaningfully activate the Rewind function.

In short, Copy works best on straightforward, always-available abilities.

Quirks that require stored energy, specific physical conditions, or deep technical knowledge are either severely weakened or outright unusable when copied.

Synergy and Strategic Use

Because Copy does not require Monoma to use two Quirks at the same time, he can chain them in rapid sequence.

This allows him to place multiple effects on a single object or situation as long as each effect is applied in a separate activation.

For instance, he can use Yui Kodai’s Size to enlarge an object and then switch to Nirengeki Shoda’s Twin Impact to create a delayed second strike with the same enlarged object.

The size remains altered while the second impact is applied, effectively layering Quirk effects without simultaneous dual activation.

Copy pairs especially well with Quirks that modify or create objects, or that place persistent effects on the environment.

Since those effects remain even after he deactivates the copied Quirk, he can switch to a different ability and build on what he already set up.

In team scenarios, this lets Monoma orchestrate multi-Quirk combos as though he were a full support toolbox.

The more he knows about his allies’ Quirks—range, timing, weaknesses—the more dangerous and unpredictable he becomes.

Monoma is a cerebral combatant who relies on planning, observation, and psychological pressure.

He prefers to manipulate the flow of battle rather than simply overpowering his opponents.

He excels at identifying key enemy abilities and then turning those very strengths against them by copying their Quirks.

He uses bluffs, taunts, and misdirection to make opponents misread his capabilities and timing.

Because he lacks raw power without a good copy, he is vulnerable in one-on-one fights against unknown Quirks.

Against an unfamiliar opponent, he first needs to understand what their Quirk does and how it behaves, which costs time and exposes him to risk.

His fighting style is therefore most effective when:

He has prior intel on enemy Quirks.

He has allied Quirks available to copy.

He can design and execute multi-step plans rather than engage in spontaneous brawling.

This approach, combined with his flair for theatrics, makes him come off as a “trickster” hero.

He is willing to use dirty tactics, heavy provocation, and mind games if it increases his side’s chances of victory.

Monoma’s lines frequently overflow with mockery and dark humor.

A few emblematic examples include:

Wishing for Class 1-A’s failure during the provisional license exam:

“Hey, did you know? The provisional license exam has a fifty-percent failure rate! I hope every single student in Class 1-A fails!”

Reflecting on main-character dynamics and self-perception:

“Everyone is a supporting character in someone else’s life, and the main character of their own life.”

Gloating about remedial exams at training camp despite having failed himself earlier:

“How strange! The so-called ‘elite’ Class 1-A has five students taking remedial lessons!

Class 1-B only had me! Isn’t that strange? So strange!”

These lines illustrate his mix of self-awareness, denial, and theatrically cruel sense of humor.

He often positions himself as the bitter narrator standing just outside the spotlight.

U.A. Sports Festival

During the first event, the obstacle race, Monoma finishes in 36th place and advances.

In the second event, the cavalry battle, he teams up with Pony Tsunotori, Hiryu Rin, and Reiko Yanagi’s classmates (in the text: Enjo, Kaibara, Kuroiro equivalents), using Copy to mount a strategy-heavy assault.

In that cavalry battle, he copies Katsuki Bakugo’s Explosion to attack and uses Eijiro Kirishima’s Hardening defensively by switching Quirks at precise moments.

This shows how he can partially mimic multi-Quirk synergy through rapid alternation, even though he can’t dual-activate.

Although he ultimately loses, Monoma proves that Class 1-B is not to be underestimated.

As a spectator, he also impressively sees through Ochaco Uraraka’s trap against Bakugo during their one-on-one match long before many pro heroes in the stands do.

Class 1-A vs Class 1-B Joint Training

In the joint training exercises, Monoma appears in the fifth round.

The participants are Izuku Midoriya, Ochaco Uraraka, Mina Ashido, and Minoru Mineta from Class 1-A versus Monoma, Yui Kodai, Nirengeki Shoda, Reiko Yanagi, and Hitoshi Shinso from Class 1-B.

Monoma works closely with Shinso to wage psychological warfare against Midoriya.

During their plan, Midoriya’s Quirk suddenly goes out of control, forcing the match to be temporarily halted.

After Ochaco and Shinso help Midoriya bring his power back under control, the fight resumes.

Monoma seizes the moment to launch a surprise attack and succeeds in copying Midoriya’s Quirk.

However, since One For All’s accumulated power does not copy, the Quirk becomes a “dud” in Monoma’s hands.

He fails to produce any effect and is quickly taken down by Ochaco’s attack.

Even after he is captured by Ochaco, Monoma continues to taunt and bait his opponents.

This ongoing psychological pressure gives Class 1-B a fleeting chance for a comeback, but Class 1-A ultimately wins the fifth round.

Second War Against the Villains

In the large-scale final conflict with the villain forces, splitting the enemy’s power becomes crucial.

All Might and the heroes ask Monoma to copy Kurogiri’s Warp Gate Quirk in order to scatter the villains and defend multiple battle fronts.

Monoma trains intensely to master this extremely difficult spatial Quirk within a few days.

He also reveals that people have always told him his Quirk is only fit for a supporting role and that he could never be a “superhero” main character.

Vlad King counters this by telling Monoma that he has always been the protagonist of his own life and that his role is indispensable.

Encouraged, Monoma successfully activates Warp Gate on the day of the decisive battle and helps separate the villain forces.

Later, he also copies Shota Aizawa’s Erasure Quirk to neutralize Tenko Shimura (Tomura Shigaraki) during the fight.

Because Erasure requires continuous line-of-sight and focus, Monoma solves the five-minute time limit by maintaining constant physical contact with Aizawa and repeatedly refreshing the copy.

His collaboration with Shinso and other support heroes in this war underscores a major theme.

Both the “villain-looking” brains and the “supporting-role-only” Copy hero play crucial, heroic roles in saving many lives.

In the comedy spin-off My Hero Academia Smash!!, Monoma appears as a recurring Class 1-B character.

He is introduced there as a “sarcastic handsome boy,” leaning hard into his role as an annoying pretty-boy antagonist.

The parody series continues his gag of provoking Bakugo, only to be knocked out by Kendo’s classic hand chop.

His personality is exaggerated for humor but remains fundamentally in line with the main series.

In the light novel My Hero Academia: School Briefs – Festival, he leads the script and direction of the chaotic play “Romeo and Juliet and the Prisoner of Azkaban ~ The Return of the King.”

The play is a mashup of very recognizable elements from famous stories, which Monoma pretends not to notice as he shamelessly plagiarizes them for entertainment value.

He plays the lead role: a cheerful prince named Romeo.

Because Monoma is naturally conscious of how others see him, he adapts easily to the stage and delivers a compelling performance of a prince who learns and grows through hardship, successfully guiding the play to completion despite multiple mishaps.

Monoma’s fashion sense and tastes hint at a possible fondness for European, particularly French, culture.

He likes French cuisine and bandes dessinées, which are French-language comics.

His hero name “Phantom Thief” matches his creative use of Copy and his theatrical flair.

He “steals” the spotlight by stealing Quirks, aiming to outshine the main hero even as a supposed side character.

The character’s design is reportedly inspired by actor Dane DeHaan’s portrayal of Harry Osborn in The Amazing Spider-Man.

This influence can be seen in Monoma’s combination of good looks, fragile intensity, and slightly unsettling aura.

In the anime, voice actor Kohei Amasaki also voices Shihai Kuroiro, another Class 1-B student.

This double casting adds a fun production-side connection between two of Class 1-B’s more distinctive personalities.

In a future epilogue set eight years after the second war, Monoma ranks 10th in the Hero Billboard Chart.

Still using the hero name Phantom Thief, he has evidently reached a level where he can copy an enemy’s Quirk and use it better than its original owner, at least for the brief time available.

This implies tremendous growth in adaptability, combat experience, and Quirk mastery.

From a boy told he could never be a main hero, Monoma becomes a top-ten pro hero whose very specialty is outdoing others with their own power.