The bud of bittersweet first love takes bloom! A mysterious boy comes to Saku Fujigaya's rescue when she falls ill on a train, but he leaves before she can thank him. After this experience, Saku never ignores strangers in need of help to emulate the boy who helped her. After Saku remembered meeting Iryu back when they were children, it brought them closer together, and might have led to something new stirring in Iryu's heart. But Saku is focused on her plans to tour the school festival with Haruki. Will their day together turn out as she hopes?