Haruka, Naomi, and Yukino attend a college for young ladies. At first glance, the three seem to be on good terms, but Haruka, the daughter of the president of an electronics manufacturer, Naomi, the daughter of her managing director, and Yukino, the daughter of the president of a subcontractor, have an invisible school caste. Meanwhile, Yukino gets engaged to Haruka's older brother, Junya. After that, everything started to revolve around Yukino, and she was not interesting to Haruka, who had been an absolute existence until then.
