Lollipop chainsaw (dxd harem x male oc edition)

Have you ever wondered if Rias Gremory was her school's head cheerleader? Well that's pretty much what she is. And she's also a zombie hunter but she kept that part of her life secret even from her boyfriend Toad who happens to be the captain of the football team. All this madness started on Rias's birthday. on her way to school, she was being surrounded by zombies. Luckily for her, she had her trusty chainsaw with her. When she reached the school, she noticed Toad running away from the zombies but unfortunately was bitten by one of them so Rias had no choice but to separate his head from the rest of his body and performed a ritual to keep his head alive. now it's up to them to uncover the conspiracy and return to their normal lives.