Medaka Box Temporada 1 Episódio 12

After Medaka goes to the hospital to treat the injuries she received from fighting Unzen, the Student Council receive a request to find a missing shougi piece from a 2nd year, Mochibaru Sasae. After searching the room and finding no trace of the piece, Akune suggests that they ask Natayama, an ex-member that has a resentment towards the club.