Night of the Werepuff is the fifteenth episode of the second season of Kappa Mikey and the forty-first episode overall.
Gonard is activating a large robot, but is confronted by Lily and Mitsuki. Mitsuki engages him in a firefight while Lily attempts to shut off the robot. She is unable to stop its activation and calls Mikey for help. Mikey is unable to get down from a tree he is climbing. Guano ends the scene.
Mikey reveals that he is afraid of heights. Ozu arrives and warns the cast that the park will be plagued for the next three days by a clothing-eating monster called the "werepuff". Night falls while Ozu is speaking, and he instructs the cast not to leave the path when exiting the park. He also warns them not to taunt the werepuff should they encounter it, especially not with a silly dance.
The cast attempt to exit the park, but Mikey deliberately wanders off to find the werepuff in order to prove his courage. Mikey eventually encounters the werepuff, but forgets Ozu's warning and taunts it with a silly dance. The werepuff chases after Mikey and eats his pants before running off.
The next day, Mikey reveals to the cast that he had encountered the werepuff. While filming a scene for LilyMu, he demonstrates a newfound ability to leap long distances and a tendency to speak in gibberish. Lily is infatuated with Mikey and asks him out, but he declines and states his intention to eat clothing.
When at home that night, Mikey goes through a strange transformation at the rising of the full moon. He grows a coat of orange-and-blue hair, similar to that of the werepuff, and begins consuming clothing. Mikey leaves his apartment and corners Yes Man in the elevator, devouring his suit and Ozu's suit that he was carrying with him. Mikey wakes up the next day thinking that his actions were a dream, until he begins coughing up clothing.
At LilyMu Studio, Mikey is nervous that the others will discover that he is becoming a werepuff. When exposed to a prop of the moon, Mikey goes through the transformation again. He consumes Gonard's clothing before running off. Ozu arrives and informs the cast that Mikey can only be cured if he is fed fur from the werepuff. Lily and Mitsuki are tasked with finding Mikey, while Gonard and Guano are sent to find the werepuff.
Gonard, Guano, and Ozu are at the park, where they plan to lure the werepuff out using a t-shirt.
Socky is at the Tatami Megastore, where he is pursued by Mikey. Lily and Mitsuki arrive and discover that Mikey has consumed large amounts of clothing. Mitsuki tries to convince Mikey to let them cure him, but Lily, having become infatuated with werepuff-Mikey, runs off with him.
Lily and Mikey become a celebrity power couple, to the others' dismay. The werepuff arrives in the park and gives chase to Gonard, Guano, Ozu, and Yes Man. Gonard attempts to communicate with it using "demon llama", which he claims is a similar language. While the werepuff is distracted, Ozu manages to retrieve a piece of its fur. They leave to go find Mikey and cure him.
Lily and Mitsuki are at the mall, where Mikey is loose and is eating clothing. The others arrive with the hair just as Mikey bursts out. Ozu stuffs the fur down Mikey's throat, and Mikey transforms back into human form. The group celebrates their success, but the werepuff arrives and runs off with Lily.
The werepuff climbs LilyMu Towers while carrying Lily. Mikey resolves to save Lily, despite his fear of heights. They fly the LilyMu jet alongside the building and lower Mikey down with a rope. Mikey manages to grab Lily out of the hands of the werepuff and pull her back into the jet. Guano then maniacally blasts the werepuff with the jet's laser. The group question him about this, but Guano states that he cannot remember why. The werepuff is seen, unharmed, standing nearby, agitating Guano again.
The LilyMu episode is finished, with Mikey arriving and cutting the robot's power cable with the orb, stopping the robot and defeating Gonard.