The butthole, or anus, or many other names I could list here, is the end of the colon which is part of the gastrointestinal system in our bodies. The ‘hole’ itself has two main sections the anus (the opening to the outside of our bodies, a ring of muscle you can feel by touching down there) and the rectum (the rectum starts after a second ring of muscle at the end of the anus, called the anal sphincter).
Both the anal opening and anal sphincter are essentially rings of muscle.
During anal sexual play a finger, sex toy or penis can be inserted into the anus and pass through both of these rings. During rimming, someone is orally stimulating that area. Some play can be on the outside or just inside the anal opening- it really depends on what feels good to each person.
The idea of ‘stretching out the butthole’ comes from concern around harming those rings of muscle from sexual activity. Permanently stretching out or damaging those muscles during lubricated, consensual, reasonably paced anal sexual play is extremely unlikely. Just like other muscles in your body, these anal muscles contract and expand as needed.
However, if those muscles are forced open or if there is trauma to the area then that could potentially damage them. This is why it is SO important to take your time when engaging is anal sex play, communicate well with your partner about what they are OK with and make sure you are using plenty of lube.
