From Crimson Moon Scanlations and Tcmanga:

A girl named Ai Sugawa, aged 16, who has a deep awaited love and fell for someone who deems to be unreachable, Naoya Senpai. He is a star in the Track and Field club and quite popular. When she was going to confess to him to help her a demon named aya the beast descends saying ''its been 11 year Ai'' Ai remains shocked perplexed about who he is with dark black wings !!!! What now ?

keep reading! a sweet lovely one-shot .