Paradise.
It was once home for him, or more specifically...it was his home before being cast out. Lucifer still felt that knife deep within his gut like a burning inferno, heightening and intensifying the rage that he felt. Despite ruling over Hell and watching over it for so long, things were...stagnant. For a long while nothing fun had happened in Hell, nothing to entertain him. Though collecting souls used to be fun, he wanted more excitement than just that. He wanted something to do. Something meaningful that'd break the stagnation.
Of course, this was manifesting in a very foolish yet potentially endearing idea. Walking right up to heaven's gates. With a spring in his step leading him there, he tapped his knuckles against the ol' pearly gates that lead to paradisio. Each tap rang out, not like a tap, but as if someone had scraped their nails upon chalkboard. In normal folk (and even some supernatural beings) it sent shivers down the spine just from its intensity alone, serving as a sort of 'ding dong, the devil's here'.
"Knock knock...who's there? Heaven. Heaven who? Heaven's ex is checking in with the winged crew. Gotta make sure daddy's running a nice resort up here unlike the resort down there. Soooo...anyone around to listen to an ol' sinner...?"