Usagi

Usagi is an extraordinary variant of the monster species known as a Fighter Rabbit, specifically the subspecies called Kick Rabbit.

This creature specializes in overwhelming physical combat, combining devastating leg-based attacks with explosive speed.

Usagi is strong enough that even monsters which Yūya Tenjō and his group hesitate to fight are taken down in a single kick.

In terms of physical ability, Usagi ranks among the strongest, but is notably poor at using magic.

Usagi seeks a successor to carry on the title of “Saint,” wandering dangerous areas according to personal whims.

This goal eventually leads to a fateful encounter with Yūya Tenjō in the Great Demon Labyrinth.

Although commonly called “Usagi” (“Rabbit Master” in Yūya’s case), Usagi has never given a personal name.

It remains unclear whether “Usagi” is Usagi’s actual name or simply a convenient nickname used by others.

Usagi has the demeanor of a strict but fair martial arts master.

This divine beast is serious about combat, yet whimsical enough to stroll into the Great Demon Labyrinth just out of curiosity.

Despite the overwhelming power and intimidating titles, Usagi is approachable and willing to teach.

There is a playful side as well, visible in how Usagi casually accepts nicknames without correcting them.

Usagi’s pride lies in physical prowess and the legacy of the “Saint” titles.

At the same time, Usagi can admit weaknesses, openly recognizing a lack of talent in magic and seeking to improve through training.

Usagi’s main weapon is an incredible kicking power, befitting the title “Kick Saint.”

With a single kick, Usagi can finish off monsters so strong that Yūya Tenjō and his companions hesitate to face them.

The species as a Kick Rabbit grants exceptional leg strength and acceleration, giving Usagi terrifying burst speed and close-combat dominance.

Usagi also holds the title of “Ear Saint,” hinting at extremely sharp perception, awareness, or sensory abilities connected to the long rabbit ears.

Physically, Usagi stands at the peak level of power in the world.

However, this comes with a trade-off: Usagi is notably bad at using magic and is far from a magic specialist.

Usagi’s main objective is to find a worthy successor to inherit the “Saint” mantle.

During one of these attempts, Usagi enters the Great Demon Labyrinth on a whim and encounters Yūya Tenjō.

After meeting Yūya, Usagi explains the situation and tries to appoint him as the new “Saint” successor.

Yūya gently refuses, not accepting the role despite recognizing Usagi’s greatness.

Instead of parting ways, they strike a mutually beneficial deal.

Usagi teaches Yūya Tenjō and Night the art of powerful kicking attacks, enhancing their combat style.

In exchange, Yūya teaches Usagi body-strengthening magic to compensate for the divine beast’s weakness in mystical arts.

Through this training exchange, they develop a unique bond where each serves as both mentor and student to the other.

Yūya Tenjō

Yūya Tenjō first meets Usagi in the Great Demon Labyrinth, where their relationship begins with a test of potential.

Though Yūya refuses to become the official “Saint” successor, he respects Usagi’s strength and wisdom.

Yūya affectionately calls Usagi “Rabbit Master,” recognizing Usagi as a teacher in martial arts and kicking techniques.

At the same time, Yūya becomes Usagi’s instructor in body-enhancement magic, turning their connection into a two-way mentorship.

Their relationship is built on mutual respect and trust, rather than a rigid master–disciple hierarchy.

Each helps the other overcome their weaknesses: Yūya refines his physical combat, and Usagi expands magical capability.

Night

Night, the wolf-like companion of Yūya Tenjō, also becomes a student of Usagi’s kicking techniques.

Usagi treats Night as a serious trainee, pushing Night to improve physical attacks and combat movement.

This training strengthens Night’s fighting style, blending natural beast instincts with Usagi’s disciplined martial skills.

Usagi’s willingness to train Night shows that the divine beast judges by potential and spirit, not by species or origin.

Usagi is called “Usagi” and “Rabbit Master” by Yūya Tenjō, but never clearly states a personal name.

Because of this, it is unknown whether “Usagi” is a true name or simply a convenient label given by others.

The titles “Kick Saint” and “Ear Saint” are official and tied to Usagi’s legendary combat reputation.

These titles symbolize both technical mastery (especially in kicking) and the position as a holder of “Saint” power that needs a future successor.