From Evil Flowers:

For Ran, love never goes well. She is having an affair with Tabuchi, her married boss, and once, when they quarreled, she was saved by Kazuya, a man she used to be in love with a long time ago. Kazuya used to be a close friend of Ran’s brother, but one day, he just disappeared. Ran had been drawn apart from him since then. After their reunion, Ran’s old feelings came back to life. However, there are many dark rumors surrounding Kazuya. Ran tries to find the truth, but a dark shadow is starting to settle over her life as well. What could be the reason for this…?!