Mamono Musume to no Seikatsu: Lamia no Baai

Long ago, Light and his childhood crush, Leimia, made a promise to meet again one day and get married. Now, years later, he is surprised to find her standing on his doorstep, ready to pick back up where they left off. Only problem is... she looks nothing like what he remembers! Leimia invites him to come back home with her to meet her tribe, but Light, puzzled about how to react to a lamia monst...