Ruby on the Cake - Hitogui Majo no Bansankai

Summary

In London, there lives a "witch" that prefers to eat only men. In order to exterminate them, an agency, known as RED, was created by MI6, the British Secret Service. Ruby Blood is a young "witch-hunting" genius who works at the agency, but she is also an ordinary girl who loves food and her family, She looks forward to the dinners her father cooks for her every day.But on Christmas night, her destiny changes forever.......Eat or be eaten, girls' suspense story!