Tweef

The anal sex equivalent of the vaginal sex queef.
Air trapped in the anal canals, rectum and colon, as a result of penetrative intercourse. This trapped productive air in normal circumstances acquires no smell and should not be confused with regular flatulence.

in fact, the transition between unscented air and scented flatulence is frequently the earliest warning that a new rectal douche is required.

We'd been fucking hard all night when suddenly I had to let out an enormous tweef for fear my stomach would otherwise explode.

I secretly let out what I thought was just a tweef, but thank God the resulting embarrassing smell was sufficient to send me to the bathroom prior to any unwelcome surprises