yep, extreme codependency, Katou feels like he can no longer live if Oda leaves him and Oda is doing whatever it takes to keep Katou with him to make him feel like he can never live without Oda again. Real twisted and fucked up
...huh. i thought katou's bruises meant they were both immortal except for wounds inflicted by the other, and then he'd try to kill oda but uhhh ok. it's my type of ending but very unearned, baffling lol