S1·E31 The Cow Says Moon

Evil Princess Irmaplotz summons fourth a cow like something milky to bite dave after he swims in the milk, thus in a month later when the moon is full, making dave a Were-Cow. After terrorizing the villagers, dave is bitten by a cat. He is bitten by an array of other things, including an Egg Beater and the Gym instructor. In the end the gang make dave bite his tongue with a sheet of paper, causing him to become a Wear-Dave. But Fang thought that he's a non-weary Dave so Dave is back to normal before Irmaplotz was surprised that the gang breaks the code making Dave back to Normal. In the next morning, Dave accidently bite Faffy thus Faffy becomes Faffy-Dave singing "Funny Bunny."