Urino's rules spark escalating arson; Hiyori supports him while Osanai gives advice as bonds shift.

Kobato remembers his encounter with Osanai when they were in middle school.

Kobato wakes up in the hospital and sees a box of chocolates with a message from Osanai.

Kobato and Osanai finally find out the whole truth and get help from an old acquaintance.