Misaki Takahashi and Akihiko "Usagi" Usami's relationship has been going well after three years of living together. However, all great relationships have issues, and theirs is only getting started. With a new competitor on the horizon, Usagi is concerned about Misaki's emotions for him. Meanwhile, Ryuuichirou Isaka has always enjoyed intruding on Misaki and Usagi's love lives, but his own hasn't been all smooth sailing—Isaka and his secretary Kaoru Asahina have been dating for a few years; however, Asahina prefers to keep their professional and private lives separate, which often leads to troubled waters between them. Nowaki Kusama and Hiroki Kamijou hardly see one other now that their careers are finally taking off. Doubts grow as the amount of time they spend together decreases.