Rin Hiigarashi, a 19-year-old woman, is the only daughter of a wealthy businessman from the Hiigarashi family. Rin has a rather irritable and somewhat hostile demeanor. This attitude developed because of a young boy adopted by her family, causing Rin to feel less special and fostering a sense of jealousy towards the boy. However, over time, Rin begins to care for the boy, even though she expresses her concern in a subtle manner.