Hoods Entertainment

Masayuki's parents have gone overseas, leaving him alone in the house. To his surprise, they have hired Sayaka, a fellow student from school, to work as his maid while they are gone. Masayuki wants his life to be peaceful, but alongside Sayaka's affections he also has to fend off the attention of his kohai, his younger aunt, and his aunt's yandere lesbian admirer.

The story begins with the peaceful daily life of schoolgirls—which suddenly breaks down when former schoolmates become zombies. The story follows the actions taken by the girls left behind on the school roof.

Haruki spends most of his time with friends and fellow classmates Airi and Ayana. All seems well, that is until Airi and Ayana form separate clubs, the Mechanical Science Club and the Chemical Science Club. The two vie for Haruki's attention and hilarious chaos usually follows all attempts to make him join.