Su is a light blue plush kitten with the folded ear tips of a Scottish fold, her soft form accented by white paws, a pale muzzle, and a sweeping tail. Pink star-shaped paw pads contrast her fur, while a yellow star gleams within her left ear. She wears round blue glasses, a ribbon tied neatly at her neck, and a beaded accessory dangling from her right ear. Clever yet gentle, her speech lilts with a habitual "~desu" suffix.

Descended from the sky, she landed atop a rooftop, discovered by her future partner after rain washed away the storm. Her glasses hold dual powers: pinpointing corrosive voids called Black Abysses and unraveling time to glimpse past events—tools vital to quelling nightmares that threaten reality.

Bound to a human companion, Su collaborates to mend disruptions in the realm of dreams. A rival challenges their missions, clashing over conflicting objectives rather than personal grudges, their dynamic defined by ideological friction.

Her name, "Su," echoes Japanese terms linked to numbers and calculation—a nod to her strategic mind, which devises solutions through methodical analysis. Though sharing a name with an unrelated figure from another story, their narratives never intertwine.

Across documented tales, her role remains steadfast: an intellectually gifted, compassionate ally, unwavering in her core traits.