precession
Explanation
This comic takes the concept of gyroscopic precession — the phenomenon where a spinning object's axis of rotation shifts in response to an applied torque — and applies it in an absurd, sexual context.
A dark silhouetted figure (possibly a salesperson or demonstrator) says "So that when I rotate clockwise around the Y axis, they go upward!" The listener, drawn as a shirtless person, responds enthusiastically: "I did not know I wanted that and now it is the only thing I want."
The caption at the bottom reads: "Gyroscopes are the ultimate form of breast augmentation."
The joke imagines applying gyroscopic physics to breast augmentation — the idea being that gyroscopic precession could cause directional movement in response to body rotation. The humor comes from the collision between dry physics concepts (rotation around the Y axis, precession) and the decidedly non-academic application. The listener's response — discovering a desire they never knew they had — parodies how people react to novel consumer technology demonstrations. It is a characteristic SMBC gag that finds comedy in the absurd literal application of a physics principle to everyday life.