When a character has their arm behind their own head while also having their hand on their own hip. Generally Standing Contrapposto, but can be done lying down as well.
A common Modeling pose. The hand on the head placement draws attention to the character's face and hair while the hand on the hip placement gives emphasis to the character's hips and butt. The pose also naturally slims their waist while having their Breasts front and center.
Not to be confused with a character simply scratching their head or looking Confused.