The fourth episode of the Nisemonogatari anime series is the fourth part of the Karen Bee story, which features Karen Araragi, one of Koyomi's two younger sisters, and a victim of an oddity that comes in the form of a bee. It was released on January 27, 2012, and was directed by Yuki Yase, who also took charge of the storyboard, with script written by Yukito Kizawa.