Momochiyo lives with his mom, Giant Mukade Momote, in an underground portion of the Hachikai Residence in Kyoto with Young Lady and Amehiko. He runs away from home due to the increased agitation of the Youkai as the Kamikui in the area is starting to break free from its bonds. He is chased all over town by Amehiko, Momotarou, and the player until Momotarou finally catches him and returns him to his mother in Hachikai Residence.
Momochiyo cannot be found until the quest "A Lost Little Centipede" is started. Once started he will first be seen in the midddle of Kyoto marked on your personal map in an alley. From there he will move to outside Kyoukotsu's Lair and then run inside. After leaving the lair, a cutscene will ensue with Momochiyo until he acquires his final resting place in his home in Hachikai Residence.