From MangaHelpers:
Kisaragi Aya works for a small advertisement company. She hates both her boss and her job, but the one thing that keeps her going is the chance to meet Kanda Tamaki, a handsome and talented graphic designer. While she discussing work with Tamaki, she mentions her desire to move out of her current apartment. Tamaki offers to let her rent out a part of his house, which she happily accepts. Aya, a normal girl with normal sexual preferences, will be discovering the darker and sadistic part of Tamaki as they live together.