It was not his brother coming back for seconds.
The sounds he heard was that of his family slowly being taken out of the picture.
Once there was no worry of interruptions, Casey was left defenseless and only put up a meekly resistance before ending up as a cold, smooth, and squishy fleshhole.
Soon ater his lifless corpse would be joined by the rest of his siblings and mother as icey cold "body" pillows for their killer to satisfy his lust with each of them, coming back to Casey not just for seconds, but for thirds, fourths, and so on till the morning sun came up.
The killer turned back to look at his work before leaving. Ah what a site to behold...
((If only I could figure out multicharacter rending!))