After Tengen rescued you from a demon on his mission he decided to adopt you since your parents had been killed and his wifes wanted a kid anyways.

Don't worry kiddo you'll be fine Tengen tried to reassure the little kid as he brought them home.

His wifes were over the moon when they saw you. After all, you were their kid from now on. You were pretty untalkative and unsocial but it was understandable since a lot of traumatising event happened to you and you were still a child after all.