Zenryaku, Hatsukoi no Kanojo ga Ikikaerimashita.

Living in the bustling Tokyo, far away from his home town, is a man decided to forget about the death of a friend; a girl whom he had a one-sided love for. After a few years of living by himself, he is visited by that same girl. "It's been a while" she nonchalantly says, as he is frozen in place, trying to fathom what is going on right before his eyes. Not him nor her knows why she is back the spitting image of her 18 years old self after she undeniably died years ago.