When you slip your dick into a fat chick (boinking her) who isn't expecting it, causing her to involuntarily let out a little "oink". She must be fat. And she must be sweaty. This is similar to when a chick involuntarily "oinks" while laughing.
Officer Jon amd Jane are going to start a boink and oink relationship..
Officer joe please let me know if you are interested in a boink and oink for my speedy ways