When the top of one's [[thong]] can be seen over the rear waistline of the pants, forming what looks like a whale's tail.  

For a literal whale's tail, see [[cetacean tail]]. See [[panty straps]] for when the straps are visible from the front.

h4. See also

* [[bikini jeans]] [i](similar-looking)[/i]
* [[downpants]]
* [[panty peek]]
* [[panty straps]]
見せTバック 見せハイレグパンツ