Tsukasa Koiso is one of the students from Class 3-2 during the second season of the anime. Tsukasa loves gossip and admires her classmate Himeko Tachibana. She has a lot of superficial knowledge about sex. She is a close friend of Masumi Yada, Ai Tsuchiya and Toshimi Shibaya. When the four of them gather together, they usually get pretty noisy
