My Little Sister Is This Cute.The Kosaka siblings head back to their hotel room to sort out their actions after agreeing that siblings cannot get married in real life. Here, Kyosuke gives her a ring as a Christmas present, and he puts it on her finger as a pseudo-engagement ring. Having already given thought into their next move, Kirino shares this with Kyosuke. Sometime later, the siblings formally acknowledge their relationship to Saori and Ruri before Kyosuke leaves to meet up with Kanako at her latest concert, where she confesses her love for him which he rejects. The next day, Kirino shows Kyosuke the box she had denied showing him previously and reveals its contents, including a photo album containing pictures of when they were younger. Kirino has Kyosuke listen to the diaries she had been recording since she was young, documenting the feelings she started to develop for him. Among them is a message where her younger self desperately asks for advice on how to be with Kyosuke. Afterwards, both Kirino and Kyosuke smile in that at the end, their relationship had finally been repaired.