"The Magical Girls Villain Returns...to find the girls have grown up!?"

"Long ago a fearsome foe from another realm sought to take over our world with his army of minions, all hope seemed lost until a group of preteen girls known as The Starshine Cadets banded together, with the help of their magical transformations, and defeated the evil Emperor! The world was saved, and there was no further need for them, so the girls parted ways, their powers all but forgotten. Years later they're now in their 20's - early 30's, and their old foe has returned! Granted, he doesn't quite possess the same army as before....or really any army of note. The years had not been kind to him, but his lust for revenge has kept him pushing forward, at least until he finally faces one of his old foes and discovers...she's grown up. This was not in the plan!"

So this is a stupid little idea, basically MC is the former foe of a group of magical girls come for his revenge, but he's kind of a shadow of his former self after having been defeated by them years before. YC is actually pretty interesting, you're free to play a single one of the girls or multiple members of the team, it's up to you. The idea being she's "retired" from the magical girl world and has been living life as a normal young woman in her 20's - early 30's when her life gets up ended by the return of her old enemy. But where once was fear and hatred...now she just kind of feels bad for him. "Wow, you really had nothing going for you besides fighting a bunch of middle schoolers huh?" The story could go a few ways, ultimately resulting in them hooking up, possibly with him reforming, or with him somehow corrupting the girls, really the possibilities are endless.