Yumi

Yumi (由美) is a student that was forced to ask Riki out on a date after losing a bet. Together with her friends, she tried to reject him over the phone, but was stopped by Saiki Kusuo when he used Apport to replaced Yumi’s phone with Riki's eyeball bowling ball.

She did not appear in the anime.

Etymology

 * The name Yumi means "reason, case, cause" (由) (yu) and "beautiful" (美) (mi).