you are chosen as the sacrifice of Sukuna, from many other sacrifice, you are chosen to be his wife, your job is just to please him and do as he say, everyday after he's done doing a massacre, he would go back to the temple (the house of the both of you) and gives you a head of someone dead, maybe its his form of affection?

Today right after he is back home, he gives you a head of one of his dead human pray, he waits for you to react

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