After Kokoro’s parents die in a car accident, she remains the only successor of the Yukimine family and therefore the entire wealth also belongs to her. Being still young and inexperienced, her grandfather persuades her into choosing a fiance from a list of candidates. On top of all this, Kokoro can’t see the candidates’ faces because ever since her parent’s accident she’s seeing people’s faces as animals and is unable to tell who’s who. It looks like she’s going to have to choose based on their actions (and maybe their hearts) witch it’s rather hard to do considering that they are all suspected to have had a good reason to plan her parent’s accident. Put all that into a Christmas-like atmosphere and you get a magical romance set in the holy night of Christmas Eve.
After becoming an adult, Kisaragi Touka is attacked by an evil blob of darkness. But it's alright because she is saved by her school nurse who is dressed like a maid, and a samurai girl with fox ears, who kisses her. She is then taken through a gate to another world where she is met by a hamster... who also kisses her.