Having lived as the second son of a temple, worshipped as a deity, and being a sheltered boy capable of transforming into a snake, Sei finally decides he's had enough of this life, and sets out to run away from home! Not being used to human society, Sei gets worn out and escapes to a grassy field where he meets and is helped by Murasaki, the reptile enthusiast college student. As the sheltered boy who longed to be "normal", Sei takes this chance to befriend the unfriendly and hard-to-read Murasaki, but their co-habitation life is riddled with misunderstandings...?!