The OVA is divided into three separate stories. The first one is called Junjou Egoist and relates to the couple Kamijou Hiroki and Kusama Nowaki who are taking a trip on the Shindai train. The second one is called Junjou Terrorist and relates to the couple Miyagi You and Takatsuki Shinobu who are having difficulty accepting the age gap between them. The last one is called Junjou Romantica and relates to the couple Usami Akihiko and Takahashi Misaki who are remembering the early days when Usami tutored Takahashi for his college entrance exams.

Source: ANN

Note: Bundled with the limited premium edition of volumes 16 and 20 of the manga.

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Prequel: Junjou Romantica 2