In the Guest Room of Twilight's castle there is a single human, he is solitary and does not speak. At least, not to them. He speaks to himself as if their was another pony in the room with him, but other than that his only interactions were nothing more than nod and a sound. But one night, as Twilight is getting ready for bed herself, she hears music coming from his room.

"I am the Walrus" from what I am seeing is mostly a free domain song. The only thing that is for sure copyright about the song is that it was sung by the Beatles