TV-Series
Description
Zen Tohno serves as a temporary homeroom teacher for Miko Yotsuya and Hana Yurikawa's class. He appears as a young man of average build with short, tousled hair, typically dressed in a button-up shirt, navy blue slacks, and brown dress shoes. Though some female students find him physically appealing, his eyes often project a tired or unsettling quality, creating an uneasy presence.

He displays a marked disinterest in people, struggling to remember names and maintaining emotional distance. This detachment sharply contrasts with his intense dedication to cats. He actively rescues strays, housing them in his apartment despite pet restrictions, and exhibits gentle, nurturing behavior toward them. His compassion for cats drives him to extreme actions, such as throwing himself in front of a car to protect a kitten.

Zen's behavior originates in severe childhood trauma inflicted by his abusive mother, Mrs. Tohno. She subjected him to relentless criticism and control, berating him for scoring 98 instead of 100 on a test and manipulating him into missing a friend's birthday party. During this time, he secretly rescued a stray cat, caring for it in hiding. When his mother discovered it, she killed the cat, discarded its body, and further vilified him. He internalized this trauma, silently accepting her cruelty without resistance.

After his mother's death, Zen began caring for strays as atonement for his inability to save the first cat. Many cats under his care succumbed to illness or weakness, implied to result from his mother's lingering spirit draining their life force. He interprets these losses as karmic punishment, persisting in his efforts due to deep-seated guilt. This compulsion led him to track down and attack a man responsible for recent cat killings, using a taser and potentially killing the individual while concealing the body.

Supernaturally, Zen is perpetually surrounded by numerous grotesque cat spirits and a colossal spectral entity. These manifestations, initially suggesting possible animal cruelty to Miko Yotsuya, trace to the cats that died under his care, tethered by his unresolved guilt and his mother's malevolent ghost. His mother's spirit manifests as a deformed humanoid entity shifting into a spider-like form, constantly haunting him and warning others "Don't look" if they observe him.

His prior encounter with Miko centered on a stray kitten adoption attempt. Though appearing well-intentioned, Miko refused, sensing the terrifying spirits around him. She entrusted the kitten to Gozuka instead, deeming him safer due to a benevolent cat spirit accompanying him. This rejection caused Zen to distrust Miko. Upon becoming her teacher, his spectral entourage heightens Miko's vigilance, though she continues to conceal her perception of the spirits.