No idea. Tried to google that but a bunch of diseases and cancer pertaining to the rectum/anus popped up...... and a certain passage as well.
The passages goes:
“If the anus, that some also call ‘ring’, twitches, it shows inspections, abuses, and the discovery of secret matters”
Hmmmm secret matters
Maybe gay porn will help lolol
To answer your question, YES. you have what you call an 'external anal sphincter' which does the twitching. During rectal exams for neurologic disorders, doctors asks their patient to squeeze while they insert a lubricated and gloved finger, a tightening on the examining finger means you have a positive 'anal wink' test. This test is most commonly used to determine if you have damage on your spine (positive anal wink test means normal), specifically your S4 and S5 spinal segments.
do assholes actually twitch?