Comment by R£I L££ on Tokyo Revengers - Chapter 270

Have you read what happened to him where he fell down the stairs and hit his head hard.  Which cause him to be in a vegetative state.  When you're diagnosed with that you can't live longer.  It's like cancer where your doctor give you how many years or month left for you to live.  And also Mikey was just a kid that time when he fell.  If he was in his 17s and fell he wouldn't be diagnosed bc he would have become more stronger as he is right now.

Shin died in another timeline where Mikey is alive.  Hope you know what you're reading right now is the Original Timeline where Mikey d!ed and Shin is alive. For us to see Mikey still alive when Takemichi met him is bc Shin time travel but Shin is completely dead now as a timeleaper so no one can bring him back. 

But now Takemichi is the other timeleaper after him we never know if he can change the future with his power where he can bring back Shin and the dead characters back who are also important for Mikey as now Mikey is his trigger