Questtion 389: Beet around the Bush

The below excerpt is believed to be the reason, according to a prominent work of fiction, about why X only has 9 major pieces of work, not 10.Question:

1) ID X and Y ( the extra blanks make it far too easy)
2) What is this a part of, ie, the original works?

It is agreed upon this night, March 26, 1827, between the undersigned, that the music of the Tenth Symphony, composed by _____X___, first born son of _________________ shall henceforth be the property of ________Y_________ and first fallen from the grace of _____. It is also understood that it is his intention to remove any signs of this music from the memory of man for all eternity. In exchange for the destruction of the aforementioned music it is also agreed that ____Y______and all his minions will remove themselves from the life of the child presently sleeping in the gutter directly across from the window of this room. This removal of influence is to be commenced immediately upon signing and to be enforced for all eternity.

_____________________
X

_____________________
Y