Lyrically, it is creepy but thought provoking.
Yeah, its as beautifull as it is strange, i don't know the Gacy story so i simply like the song for its musical merits.
John Wayne Gacy, Jr. was a serial killer and rapist who murdered over 30 young men and hid them under his house. http://www.crimelibrary.com/serial/gacy/gacymain.htm