Happy New Year! This story needs another bump for another holiday. 🙂
I was trying to quantify to myself why it's such a good story. Is it the relentless tickling? Is it the public humiliation during the tickling? The forced orgasm? Maybe it's the the fact that Peggy does "break a rule" and her "punishment", while severe, is a little more forgivable (in a fantasy story only, of course). Or maybe it's because the story ends with an obvious suggestion that much more tickling punishment awaits poor Peggy (sometimes what we don't see is more effective than what we do see).
Whatever the reason or reasons, many stories - good and bad - have come and gone since, but none have topped APH. If there was a hall of fame of tickling fiction, this would have to be the first inductee.