Tayutama: Kiss on my Deity

The story follows protagonist Yuri Mito, the only son of the local priest at Yachimata Shrine. After a series of events during spring break, Yuri meets Kikuramikami no Hime, the guardian of a mystical relic in the woods near his school. She explains the strained history between humans and the Tayutai, a mythical race sealed within the relic due to their potential threat to humanity. To bridge the gap between their worlds, the goddess reincarnates as a young girl named Mashiro and entrusts herself to Yuri. However, the relic is accidentally destroyed, releasing the Tayutai. Particularly dangero(Storyline via IGDB)