Gintama: Season 7, Episode 20

7 - 20: Love is a Roach Motel

After inviting Otae to the festival and being rejected, Kondo rampages around, taking his frustrations out on happy couples there. In an effort to hide the fact that the one making the scene is the Shinsengumi chief, Sougo and Hijikata convince him to wear a disguise. A short while later, Kondo runs into Otae, who doesn't seem to recognize him in his cockroach mask.