Clannad - Season 1 Episode 10 The Girl Genius' Challenge

Since no new members have joined the drama club, Tomoya goes to talk with Kotomi once again about joining. Tomoya takes her around school and helps her introduce herself to people to make more friends. Tomoya takes Kyou, Ryou, and Kotomi to the drama room after school, and after a round of introductions, Tomoya asks them to join the club. Kyou initially passes on the chance, but ends up giving in after her sister says she wants to join, and Kotomi joins as well. During the meeting, Kotomi leaves when she hears someone playing the violin, though when she is given the chance to play it, she is painfully horrible.