OK, I just read the last chapter ( 269 ) of Tokyo Revengers, if you haven't read it don't continue reading this because there will be spoilers and theory.
Well, so as we could understand Shinichiro did not go back to the past to prevent Mikey's dark impulses but to prevent the fall and therefore Mikey's vegetative state. Therefore, this is the original timeline, is as the chapter says, the most heartbreaking.
Mikey is alive, however the injury he suffered has made him vegetative, like a plant. He therefore has no more consciousness, he no longer thinks, no longer reflects, and no longer feels any feeling. (It really hurt me because my uncle is in the same situation)
So coming to the theory, I think Shinichiro became a health care provider (He helps people with reduced mobility and handicapped people) I say that because of the badge he has around his neck. Otherwise this badge is simply a pass. However I rather think that he became a "nurse" for Mikey.
Second theory, Mikey's dark impulses are after-effects of his vegetative state, this is unlikely, however it must be taken into account. Mikey's dark urges don't seem to cause him to feel any empathy or emotion, which is very close to his situation in the original timeline. Also, Mikey's eyes in this chapter look a lot like the eyes that Mikey has been discussing for several chapters.
Third theory, somehow Haruchiyo knows about the first timeline, possibly Shinichiro from the future who told him after Mikey hurt him, which allowed him to forgive Mikey for this. what he did to her. which could also explain what he said to Senju "That she doesn't know the truth"
That's all I had to say. This is the worst chapter I've read in all of the manga combined. Being in a vegetative state is far worse than dying, is saying this is the original timeline. I try to reassure myself by telling myself that it's in the past but I can't stop crying.
Bonus theory, I think the character on the cover of volume 30 is going to be Shinichiro or Takemichi (Probably Shinichiro or both at the same time)
