Kei Enjoji  

Kei Enjoji, the protagonist of Kizuna, isn't legally related to the head of a yakuza group. This forces him to leave his family home. Following this departure, he encounters Ranmaru and develops romantic feelings for him. Despite not being connected to the chief of the yakuza, a rival gang attempts to assassinate Kei, but their efforts are unsuccessful. Afterward, Ranmaru is left incapacitated and believes that he will never walk again. Kei vows to be his left arm and leg, urging him to recover because he loves him deeply. With great effort, Ranmaru eventually regains the ability to walk. This marks the beginning of their romantic relationship. Later, Kei discovers his younger brother Kai, who is legally related to the head of the yakuza group. Although they initially have conflicts due to Kai's attraction to Ranmaru, he ultimately forgives them when he sees how much Kei and Ranmaru care for each other.