Setsuna is a young, beautiful woman, recently married and happier than ever. However, she is also a professional assassin—something that easily sets her apart. Nonetheless, her husband sees nothing but a doting and loving wife, one that takes pride in her cooking skills and acts like an unexpected protector of their home.

Given that Setsuna's primary skills lie in wielding weapons, her murderous intent can easily slip out at the most unpredictable times. But with her smitten husband by her side, Setsuna learns to use her quick reflexes to enjoy mundane things and savor every ordinary moment—even if they are not the most average couple around.