Don't know if this thread was meant to include songs, but The Black Dahlia Murder had a demo, and later a song, titled, What a Horrible Night to Have a Curse. The lyrics don't reference Castlevania directly, but were obviously inspired by the series:
"Into the tower, never go, the horrors multiply
Gears can mince the strongest ones, leaving heroes paralyzed"
Other verses go on to describe different aspects of the series.