Kagetsumugi is first seen at the entrance of the Puppeteer's Tower introducing herself to Luka, Luka asks her for Magical Thread but she says that only Puppeteers can use that item but she offers it anyway for the desperate Hero before Alice/Ilias drags Luka out of the tower. After Luka and party leaves and starts discussing what they should do next, the focus shifts back inside to Kagetsumugi who is speaking with someone. After an ominous exchange, it’s revealed she is working with Black Alice. She’s creating an army of powerful puppets for the Black Alice faction so they can assume dominance in the war for the Monster Lord’s Throne.
Kagetsumugi is actually the fourth puppeteer. The first was chosen by Black Alice 500 years ago and they’ve been perfecting their technique since then.
She is an extremely powerful puppeteer, armed with four Monster Lords in her doll collection. Goddess Ilias, despite not having seen her creations, once stated that Kagetsumugi would very easily overpower La Croix.
She is last seen talking to La Croix about Black Alice and warns her that she shouldn't be trusted and later meets up with Luka and left.