Richard Milhous Nixon was the 37th President of the Former United States of America, and frequently ran into time travelers and aliens. He was not a good person.
Nixon was once debriefed by government agents about his interactions with time travelers, but he lied so much it was hard to make out the truth. He met Mr. Scratch in a Denny's.
Nixon was later visited by Lady Aesculapius and Blanche on Christmas Eve after he had resigned the presidency, so that Blanche could apologize for trying to murder him. Nixon refused the apology, and Aesc gave him coal in return.
He referenced having met "those British" time travelers.
Concert at Dusk
The Denny's Crossroads and Mr. Nixon