The class trip descends into chaos when the group gets lost in the mountains. Uka is wrongly blamed for the disorientation, but Kai steps in and calms the heated atmosphere. As the class desperately searches for a way out, Uka spots a heart-shaped cloud formation—a symbol that emotionally unites the group and offers hope. Back at school, Uka’s classmates surprisingly cover her desk with small gifts, a gesture of appreciation for her quiet care during the trip. However, Uka’s joy is dampened when her middle school yearbook surfaces, revealing her past as “Stony”—a nickname that reflects her isolation and emotional numbness at the time.

Kai encourages Uka to confront her history rather than suppress it, emphasizing that her past has shaped the person she is today, someone who is now respected. Meanwhile, Marin confesses to tampering with the trail markers out of jealousy over Uka’s closeness to Kai, prompting Tomoya to critically question Uka’s relationship with Kai. He warns her that her bond with Kai might bring not only support but also unexpected conflicts.

Amid rumors about Kai’s alleged past with Serina Kanno—a popular, radiant former classmate—Uka grapples with uncertainties about her feelings and her place in Kai’s life. Despite her doubts, she resolves to cherish her current friendships and her tender connection with Kai. The episode culminates in an ambivalent moment when Uka accidentally encounters Serina, whose charming demeanor and undeniable presence create an undercurrent of tension.