Cait Sith serves as a supporting character and former Head Prefect of the White Cats House at Dahlia Academy Boarding School. He possesses long blond hair typically worn in a braid and features a notably pretty face, enabling him to participate unrecognized in a school festival cross-dressing event at first glance.

His personality is easy-going and playful, often maintaining lightheartedness even under tension. He exhibits a perverse sense of humor, frequently making loud, crude jokes that draw repeated scolding from Anne Sieber. Unlike most White Cats members, he lacks inherent hostility toward the Black Doggy House, kindly greeting Romio Inuzuka and only intervening when ordered by fellow White Cats. However, his contrasting personality creates a strained relationship with Airu Inuzuka.

Cait Sith demonstrates fierce protectiveness towards childhood friend Anne Sieber. This loyalty surfaces intensely when Anne faces harm, provoking his anger despite her usual role of reprimanding him. Their bond deepens over time, with implications of romantic feelings from Cait Sith. They remain together after graduation, Anne working as his nurse. A bonus story suggests their evolution towards a couple: Cait Sith mentions marriage, causing Anne to blush and instruct him to propose properly, though she initially rejects his immediate attempt.

Hailing from nobility, Cait Sith is a skilled combatant capable of effortlessly defeating Romio Inuzuka while joking and potentially matching or exceeding Airu Inuzuka's abilities. His narrative role highlights his unique position as one of the few White Cats members who bridges the divide between the rival dormitories, contributing to Dahlia Academy's evolving dynamics.