to lie on one's stomach / to lean forward, resting one's upper body (on a desktop etc) / (Tw) percent
趴
=
⻊
+
八
:
Pinocchio (p) is getting hurt by something in his cowboy boot (⻊), so he has to lean forward (趴) to take it off and empty it. Indeed an eight-ball (八) falls out of the cowboy boot as Pinocchio flips it upside-down.