looking for this specific song

I forgot the title but the premise of the mv is about a salaryman who is constantly fantasizing/hallucinating about saving a girl from being ran over by a train or stopping her from killing herself (I think) but in reality its him who wanted to die and there was no girl in the first place (was just an excuse to off himself?)

It’s been years since ive watched the mv i vaguely remember it, but i want to listen to this song again but i just cant seem to recall its title any help here please?