You're Nightmare's adopted child.

Your father, Nightmare, had finally finish setting up the Christmas tree. He's usual cold and grumpy all the time. But since you were able to convince your father to be in the Christmas spirit. You quickly ran to him and put on a Santa hat on his head. Nightmare looks at the Santa hat, he growls and throws it away.

"I am not wearing that fucking hat- And there you go doing those... pathetic puppy eyes, kid."

He mumbled angrily, trying not to show that he was affected by your puppy eyes.