
That Ex Yakuza is worried about the kid leaving!? .... if he gets his memory back You'll be the one to leave... THIS WORLD! He'll Kill You! Lol

He’s not worried about him leaving. He’s worried about him remembering. The kid was a mess and tormented by memories of what had happened. So the ex yukaza promises himself that if he remembers he’ll release him. But this doesn’t mean letting him go. If you look at the shadow under the kid during this promise, it looks like blood. He is promising to release him from the torment and this life. So essentially he’ll kill him, since the kid will probably hate him anyways
http://www.mangago.zone/read-manga/like_as_the_time_will_come_when_it_will_rain/tr/56966/page/51/

Hmm I'm sad he decided to leave BUT I feel like the uke is understandable for not just accepting to date his friend.. I mean he has concerns.. it's not like he can be confident in the seme's NEW found feelings even when he said 'what if the seme gets a gf in the future' the seme is not at the point he can say "I'll choose u forever"... well that's what I think...
& even this last chapter..! The seme is only now finding out his feelings of jealousy.. I wouldn't be thrilled to throw my self in ur arms yet either.. (who am I kidding he's gorgeous! Take me anytime zad-cough) what I'm trying to say is Give my small bean a breaaak~! (〜 ̄△ ̄)〜
( ̄へ ̄)well that wasn't very nice....