Suspicious about the relationship between Haruka and Yuu, Mitsuki asks their classmates, Yuzu Iizuka and Kaede Ikeno, to keep an eye on them and make notes any suspicious behaviour. Later, the girls get together for a test of courage, where Mitsuki attempts to tail Haruka and Yuu, but gets mistaken by Yuu for a ghost, leaving her so scared that she asks Haruka to kiss her to calm her down.

Haruka and Yuu have a lengthy phone call leading up to the New Year, with Mitsuki also getting a brief opportunity to speak with Haruka. As the New Year rolls in, Yuu gives Haruka a kiss over the phone. Later, as Mitsuki becomes jealous of Haruka and Yuu linking arms with each other, she, along with Kaede and Yuzu, follow them to a park, where they almost catch them kissing. When Mitsuki trips up, Haruka manages to catch her, with Mitsuki inadvertently kissing her forehead in the process. Afterwards, Yuzu talks about her experience with learning to ride a scooter whilst Kaede laments the trouble she has with her siblings.