Stop!! Hibari-kun! - Season 1 Episode 29 Hiroko's Lost Twin! An Explosive Love Story!!
Overview: Kōsaku saves a girl from delinquent members of Kokuryu High Schools boxing club, until Hibari beats them up instead. A strange man harasses Tsubame and Suzume then breaks into the Ōzora house and peeks on Hibari in the bath. Private detective Shirachi Kogoro discovers Hibari is a boy.