BeckiLou

Need help going insane: anyone know the name of the anime series about a world where people went to school to become magic knights to battle a demon lord. The protagonist is one of the knights who now works at an electronic store because the demon lord was defeated and there is no more need for knights. The demon lords daughter comes to work at the store because she doesn't want her fathers old job. the two end up as room mates and fall in love but the series ends when she is forced to take up the demonic power and he has to save her by reminding her she actual likes working at the store. It's called something like: I was supposed to be a knight but now a work in a store. Help please.