End

i think its basically saying bum ran out into the road when the walk sign was off and he's going to get hit by a car

SPOILERS










basically, sangwoo died the same day bum tried going to the hospital to see him. the thing is, bum has forgotten sangwoo's face (possibly due to trauma), and he wants to remember but really can't. sangwoo died by asphyxiation (the grandma might have killed him). We assume that Bum died as well at the end.

When Bum took Sangwoo’s ashes he went to the old house, he was crying and was trying to remember Sangwoo’s face but couldn’t. Suddenly he became delusional and started seeing/hearing Sangwoo. Bum started chasing after him but suddenly saw him with a girl (I think he’s just imagining) which shocked him. Nevertheless, he continues running across the street which’s traffic light was turning red (meaning he cannot cross)
he most probably got hit by a car since it ended suddenly for all the events just prove it.

(⊙…⊙ ) Basically the grandma killed sangwoo, bum is depressed knowing that is how he actually died, and I believe bum is now hallucinating...that he he is seeing sangwoo let's hope he doesnt get run over..
.and yeah I get it bum is depressed because no matter how much of dick sangwoo was to him Sangwoo was the only one who still payed attention to him in his own twisted way while everyone else look down on bum.(╯°Д °)╯╧╧

Thanx you it really help me (づ￣ ³￣)づ