Ruu-kun is Climbing the Chimney - S1.E2

It was Miyu's first day at her new school. She finds out that Kanata has a fan club, and he is the class president. Miyu meets Christine Hanakomachi, a half-French girl who fancies Kanata. During class, Miyu spots Ruu flying outside. Kanata and Miyu chase after Ruu. Ruu ends up climbing a chimney, forcing Kanata and Miyu to climb it too.