Kojirase Tensei Maou to 7-nin no Oshikake Otome no Ragnarok System

Rintarou, a renowned hero who helped save Japan from being taken over by demons, has become an unconfident university student. Though he still has his incredible abilities, there's one thing he doesn't have--a girlfriend. But one day, a princess suddenly approaches him and asks to be his wife, his girlfriend...or even his friend with benefits!? (Source: Yen Press)