A student in class 1-A whose Quirk Hardening allows him to harden his body to become nearly invulnerable. His Hero name is "Red Riot," inspired by another hero, Crimson Riot, whom he admires. (Source: Wikipedia)

Gabimaru the Hollow (がらんの画眉丸, Garan no Gabimaru) is the main protagonist of the manga series Hell's Paradise. He is a shinobi assassin formerly from Iwagakure and one of the few death row criminals sent to Kotaku to acquire the Elixir of Life for the shogun. He is a very calm and serious person who is convinced that he has no feelings. Therefore, he behaves monotonously and only talks when it is necessary. However, his true personality is revealed when he is alone with his wife. You can tell that he is very shy in front of her and that's why she can easily tease him. His wife is the only person he deeply trusts and cares about because he is madly in love with her. He is known as Gabimaru the Hollow, mostly because he kills his victim within seconds without feeling guilty nor showing mercy. In fact, he was born to kill. In conclusion, he was arranged and agreed because he saw it as an order. Later he met his wife, who taught him that he is not empty and just buries his feelings deep inside him. It is also shown that Gabimaru is suicidal but ultimately regains his will to live because he wants to meet his wife.