The Student Council and S.A challenge each other to see who will organize the upcoming school festival, but Hikari and Kei end up arguing; Hikari joins the Student Council's side and Akira soon follows. While Kei takes them all on single-handedly, Hikari learns that he has always done everything alone.

The S.A head off to Hawaii for their summer vacation, but end up playing "family" to Chitose, the spoiled and demanding son of a client for Ryuu's family. He is particularly harsh with Hikari, but she is determined to make sure he has a good time, even if it means being the dog in Chitose's family.

Having lost, yet again to Kei, Hikari will have to spend the day with him. However, Kei's father takes him to Shanghai. In his absence, Tadashi asks Hikari to be his girlfriend, or at least pretend to be in front of his mother, the Director of the Hakusenkan.

Kei has recovered from his fever and Hikari must go on a date with him. Things don't seem to be doing so well, when Hikari learns that Kei's father has arranged a marriage between him and Sakura Ushikubo.

Hikari meets Aoi Ogata, a member of the Takishima Group who finds Kei important to him and is willing to do anything for Kei. When Aoi decides Kei is better off studying in London, Hikari must prove she's worthy of being Kei's rival. However, this meeting with Aoi causes Hikari to think about her true feelings for Kei.