The oneshot is about the Male mc going on a hiking trip in which (for reasons I dont remember) starts talking to his dead childhood friend who is in heaven. Where they have their emotional back and forth. She explains that when your remembered in heaven you get paid everytime your remembered. He gets over whatever trauma/emotional thing. Then he had discovers a comet (?) I believe and names it after her for a decently satisfying end. Sorry for being vague but this just popped into my head today and it was only saved on my kissmanga list (which is now very dead) so I ask for your help orz.