一场华丽的化妆舞会，青春小正太Lucas却吓跑了所有朋aaa。因为短短几秒钟，乖巧懂事的他变成了一个长着翅膀的超级大怪物！而他自己也被吓得张皇失措。气愤父亲隐瞒家族身世之余，Lucas偷拿到一张神秘地

A boy is possessed by Byleth, the demon of the incest. He wants to madly love his sister, but his tr