Help me?

Help me find a shounen ai manga where guy A almost got hit by a truck but guy B saved him. B died actually but he can't move on and only A can see him. Then A trying to help B to move on bc he felt guilty but then A started to have a feeling to B.. at the end (I can't rmbr the detail how B get to move on) when B about to disappear, A tells B that he loves him while crying and begging to not going. B tells A that he loves him too but he can't stay bc he's already dead. Then A says he wants to dead so they can be together. B got mad and tell him if he really loves B then he gotta let B go. B makes A promise to keep living his life and blah blah blah A finally let B go and says he'll always remember him.. B just smiling and then kiss A,, and B says me too and he disappears.. it was rly sad ending and I really feel like to reread it now so if anyone know the title ols let me know