[Korvax]

Hi i need your help locating an hentai/manga. i remember it was about a dude in school that has sort of "angel" girlfriend? he also had a male friend who was jealous? [the dude was wearing glasses]. so the glasses friend lured the main dude to a room which then he revelead himself to be a female succubous. it went something like that.
if you could help me find it , it would be much appreciated