Poseidon (ポセイドン) is a supporting character in Sleepy Princess in the Demon Castle, voiced in Japanese by Takeo Ootsuka. The series' music includes "Maoujou de Oyasumi - Opening / OP Full 「Kaimin! Anmin! Suya Rhyst Seikatsu」", "Sleepy Princess in the Demon Castle Ending Full - Gimme by Oresama".
