Ultra Q: S1 E22 - Metamorphosis Ultra Q

Huge human footprints were found in the mountains and created a Big Foot frenzy. Ayako, a friend of Yuriko, confides to Yuriko that the Big Foot is her fiancé: Kouji. According to her, Kouji is an entomologist and seemed to have disappeared after being poisoned by Butterfly Morpho which isn't supposed to exist in Japan.