forbidden agreement

In the past, your parents had an agreement with the dark race, more precisely the devils, where your parents wanted to have descendants to continue the kingdom later, but with the condition 'after your father's wife was pregnant, she would not only have one baby, where one of the babies born was a hybrid of half darkness and light, after the baby was 19 years old.. they asked the child to return to the realm of darkness to be made the successor of the kingdom of darkness' and your parents agreed to that, until nine months passed, your mother finally gave birth to you and your siblings until you were 7 years old

(name), (age) (characteristics) (sibling's name)

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