Brother, Sister, Lover (兄、妹、恋人Ani, Imōto, Koibito) is the special unaired OVA of the Kono Naka ni Hitori, Imouto ga Iru! anime series. It was released by Japanese production company Media Factory alongside the entire series on DVD and Blu-ray in September 2012.
Miyabi takes advantage of Shogo over the girls who wish to get close with him under the pretense of being siblings and adds that she will choose on who she will approve as Shogo's girlfriend and future partner. In response to this Mei and Ikusu hold a dating contest on Shogo where Miyabi will choose the most suitable partner for her brother from Konoe, Rinka, Mana, Mei and Ikusu. During the dates, Miyabi continuously distracts and drags Shogo away from the girls out of jealousy. Meanwhile, in Konoe's turn, she takes both Miyabi and Shogo out to an amusement park. Ultimately, Konoe brings the group to a bridal experience fair where the girls wear wedding dresses to get a first-hand experience of being brides. On Konoe and Shogo's wedding photo, the pseudo-couple allow Miyabi to be with them at the picture. Afterwards, the other girls, donning their wedding outfits, ask on who will Shogo choose next to take a wedding picture with.