My turn for a question:
Why do my nuts always require a scratch whilst in mixed company?
KB
You have Darts.
They are little critters that live in your anus,
The Dart out and bite you on the dusters and then Dart back.
You have a rare case of them I'd say, because they are usually know to be found on teenage boys.
This has been a community announcement in the hope that some may be able to live with this terrible and sometimes embarrassing condition.
Alternatively, you could get someone else to scratch for you. This would divert attention away from you playing with yourself.