Enku, known in Chinese as Yan kou or Yen k'ou which means "flaming mouth," is a hungry ghost that resides in the Preta realm from Buddhism. One Enku came across Ānanda and told him that he suffered from flaming mouth due to greed in his past lives. This lead Ānanda to learn of the Hungry Ghost Ritual (Fang Yan kou).
"A type of preta, residing in the hunger realm of the six Buddhist domains. It cooks and eats insects out of the air with the fire it spits out, but its insatiable hunger is its eternal torment. Enku are small-wealth pretas, and are allowed to eat some unclean things; other preta are forced to eat feces or burnt bodies."
—Shin Megami Tensei IV profile
Enku can be found in Tsukiji Hongwanji during the entry test. Attempting to recruit it here will result in it blowing on the candle that Flynn must keep lit during the entrance test. Enku can teach Flynn the Fire Breath, Damascus Claw and Energy Drain skills through its Demon Whisper.
Shin Megami Tensei IV Apocalypse
Enku can be found in Shibuya. It can teach the Fire Breath, Damascus Claw and Maragion skills through its Demon Whisper. Enku benefits from learning Fire and Darkness skills.
Devil Summoner 2: Raidou Kuzunoha vs. King Abaddon
"A ghoul from the hunger realm of the six Buddhist hells that spits fire. It can cook and eat insects from the air, but is eternally tormented by its insatiable hunger."