The navel tickler!

classic clothes, partially undressed to fully expose her navel and midriff, arms tied behind back, bare midriff, disembodied hands tickle, the hands' fingers have contact with her navel which tickle her and she breaks out in mirth, tickling, navel tickled, tickled with disembodied hands, finger inside navel, finger in navel, laughter, tickling, she laughs happily, laughter