Guts is the protagonist of the story. He is a tall, muscular man with a huge sword called the Dragon Slayer, a prosthetic left forearm that has a magnetic grip which also conceals a cannon. Guts is a tragic hero; he is born as one who may be able to struggle against Causality, but seemingly unable to affect it on a large scale.

Fifteen-year-old yakuza leader and strongman. When his father died, he was adopted by his uncle who saw great potential in him. His grip is so strong that if he grabs an opponent's arm, he can cause it to explode from restricting the blood flow. He is also a street fighter and it is unknown if he has trained in martial art styles. He broke Yuri Chakosky's arm, thus ending his boxing career, but when then cross paths again they hold no grudge against each other understanding each other's warrior spirit.

Guts