Troubled by guilt over a past disaster, a teacher proposes a coed experiment after talks of a school merger stall.

With the students struggling to get along, Heisuke suggests a cultural festival; details about his role in a 14-year-old chapel fire emerge.

Heisuke and Satoshi recall their doomed love triangle; culture festival planning moves forward, but the merger faces new challenges.

Yuko's father angrily reflects on the aftermath of the chapel fire; romance blossoms between students; Risa tells Handa who she wants to marry.

Furui faces an unexpected consequence for dating Birken; his classmates find a creative way to get revenge on his behalf.

Nakai is off to a decent start in the race, but something is on her mind; Satoshi shares a hunch with Heisuke; Nakai shares shocking news with Ebisawa.