'Yoo Sera', who has been possessed by the 19+, spoiled, confinement-themed reverse harem game that she has been secretly enjoying. Not only has she been possessed by the villain 'Sera', who is not the main character, but also gets trapped in the same house as the male protagonists who detest her... The escape condition here is to guess who the culprit is who locked her up. In order to get information and survive, she has to seduce the male protagonists with her body..!! Will 'Sera' be able to escape safely?