soulmate (nightmare x were-demon reader)

It always happen every were-demon's 19th birthday they get their soulmates eye and have their soulmates power . y/n l/n is a hybrid between a wolf and a demon but then one of her eyes turn dark purple .when she and her demon sis chara are being attack she sees a skeleton with dark purple eyes called 'nightmare ' . she hides her purple eye . but what if he finds out , will he love her ? ^cover art mine^ some art not mine