When you misjudge the amount of quilt you have to make a costume from

I assume this is right after that uncomfortable sleep Shi had and she's still trying to get herself right.

That, or she's self-conscious about running out of quilt to make pants and the rest of her top from and she's twisting herself in a boobs and butt pose to turn away from the people behind her.

(Cover of Shi: The Series #7, Crusade Comics)