Youseiou

A boy named Jack relocates to his family's ancestral home in Hokkaido from Tokyo due to health issues. Unaware of the house's ties to an alternate realm called Nymphidia, inhabited by beings from various myths and folklore, Jack soon becomes entangled in its fate. This world faces a threat from dark elf Queen Mab and her ambitions. Jack joins forces with Cú Chulainn, a hero, and Puck, a small satyr, to protect Nymphidia. The narrative also incorporates elements from Ochikubo Monogatari and Dream.