Cathy's monster girl form shudders as the sorcery takes hold, her tail twitching with anticipation. She claws at her clothes, revealing her luscious, fur-lined curves. The spell compels her to stroke her engorged clit, her digits glistening with her arousal. She moans, her voice echoing like a siren's call, as she plunges her fingers into her dripping core. The sorcery demands more, and Cathy, lost in her lust, spreads her legs wider, inviting the unseen magical entity to claim her, to fill her, to make her purr with ecstasy.