My bad. 90 percent sure it was on this site within I'd say within a year ago. Was a short story. Pretty sure there were no additional chapters and it was a one off. I think the girlfriend got off on the boyfriend wearing in front of his family, in which he did not. Pretty sure she made him wear it.
Story ends with the family member noticing that he messed himself as they were leaving but only makes a joke about it and does not gather attention to others about it