KNMD-081 The mother-in-law who fell for aphrodisiacs... Megumi Meguro.

Yusho and Kitayama are classmates and best friends. They weren't particularly outstanding students, but they had a secret. They conspired with their chemistry teacher, Kita, to drug female teachers and students with aphrodisiacs, leading them into sexual acts. Initially, it was just for fun, offering up female friends, but Kita gradually became domineering, even saying, 'If you don't regularly provide me with women, no credits!' Eventually, Yusho's stepmother Megumi became the target of their malicious scheme...