Gastro

Gastro is a tall, striking assassin from France who is most known for his wild spiky hair and bizarre habit of tasting his guns with different foods and sauces. He is an expert shooter, specializing in executions by gun, and stands out as the only ex-soldier among assassins hired by Akira Takaoka. Despite his toughness, Gastro actually has a sense of right and wrong and is uncomfortable with harming ordinary middle school students. During his big fight in the concert hall of the Fuku-kuma Palace Hotel, E Class manages to outsmart him, resulting in his defeat. After everything is over, Gastro decides to consider a new life, possibly as a tsukemen noodle shop owner, showing there’s more to him than just being a contract killer.

Gastro is a tall man from France.

His look is easy to remember because of his wild, spiky hair.

He always carries different types of guns, including automatics and machine pistols.

He often has food or seasoning on his guns because of his strange habit.

Gastro is usually calm and has common sense.

He questions hurting regular students because, deep down, he is not completely cold-hearted.

He has a very unique habit—he licks his guns with different flavors to find "the gun that feels best in his hands on that day."

For him, tasting the guns is also a way to check their condition.

He is a former soldier with a lot of battle experience.

Akira Takaoka hires Gastro as one of the assassins to go after E Class.

Gastro is an expert marksman who specializes in shooting and executions by gun.

He can quickly tell where hidden enemies are and what they might do next, thanks to his sharp instincts from his military days.

He handles many types of guns with skill.

The Hotel Concert Hall Battle

At the Fuku-kuma Palace Hotel, Gastro faces all of E Class in the concert hall with his magnum revolver and a loading clip.

He falls for a distraction plan by Korosensei and a trap made by Sosuke Sugaya using a dummy.

Ryunosuke Chiba shoots a revolver at a metal fitting, breaking a hanging light which drops on Gastro.

Rinka Hayami uses this moment to shoot Gastro’s gun out of his hand, leading to his defeat.

Surrender and Later Events

Gastro gives up after losing, revealing he wasn’t fully sure about hurting normal kids, even on Takaoka’s orders.

He is taken to the Ministry of Defense for questioning after the incident.

Since he didn’t try seriously to hurt the students, he is not punished and is free after.

Visiting the School Festival

Gastro later comes to Kunugigaoka Middle School’s school festival.

He samples the tsukemen soup by dipping his gun into the broth, sticking to his usual weird hobby.

After Korosensei

After Korosensei is killed, Gastro starts thinking of opening his own tsukemen noodle shop, using what he "learned through taste" in his assassin days.

Hired by Akira Takaoka with other assassins, but is the only ex-soldier.
Faces off against E Class, especially Rinka Hayami and Ryunosuke Chiba.
Shows respect for E Class after his loss, sending them his own kind of encouragement.

Gastro’s voice actor is the same as the main character in the author’s previous work. He also appeared again thanks to a “no self-restraint marketing” event in the anime.
During the same TV season, two of his works aired thirty minutes apart, making it "Koyasu Hour."
He has a list of "gun dishes," such as ume jam gun, tsuke gun (dipped in tsukemen sauce), and more.
In the “Graduation Album Time” episode, Gastro seriously thinks about opening a tsukemen shop.

Weird Gun-Flavors

Gastro’s habit is to lick guns with foods like plum jam or tsukemen soup.

This is not just for fun—he does this to check if a gun feels right to use.

He’s tried many "gun meals," such as meat gun, unagi gun, egg gun, and seasonal strawberry sauce gun.

Quotes