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Cerberus of Forested Silence
First appeared in Touhou 19: Unfinished Dream of All Living Ghost as a boss and playable character.
Enoko is an immortal yamainu with dog ears and three tails. Her hair comes in two tones, purple and white/light grey. Notably, she has two bear traps, one on each arm, which opens and closes depending on her hand movements.
Enoko works for the Keiga Family as part of their operations to take over the surface world. In reality, as with Son Biten and Tenkajin Chiyari, she is a spy whose true allegiance lies with Nippaku Zanmu. She was tasked with sabotaging the Keiga Family's invasion plans from within by playing them for time as part of Zanmu's gambit to prevent a surface war.
At some time in the past, prior to her acquiring a humanoid form, Enoko saw a young Kirisame Marisa when she first ran away from home into the Forest of Magic.