The residual poop inside the anus even after wiping and thinking you're clean from defecating. The toilet paper is clean and you feel as your butthole is clean, but you're actually not.
The after effects of resi-dook is when your butthole itches and sweats from trying to clean itself. You need to go and re-wipe to help rid the resi-dook.
I took a huge dump an hour or two ago, and now my butthole itches and is all sweaty from the resi-dook inside. I need to re-wipe!!