Togainu no Chi - 1x09 - Season 1, Episode 9- Followmy.tv

Keisuke shows Akira all the tags that he gotten, and stating his desire to see more emotions, particularly the “troubled, agonized, dying” face. They begin to fight, throughout the battle Akira tells Keisuke how he really felt all this time which angers Keisuke even more. Akira gets his weapon knocked out of his hands causing him to get cut and bleed. Some blood gets onto Keisuke’s face and mouth which causes him to suffocate. Akira get some black flashes of his past, and snaps back into reality. He finds out that Keisuke is still alive and brings him to a bed, Akira watches over Keisuke until sun rise where Rin finds them and takes off with their tags in order to fight Il re.