During the Tanker mission, calling Otacon while staring at a bikini girl poster on the inside of a locker will cause Otacon to reprimand Snake, who will be pulling a face of awe. Hiding inside the locker and pushing Snake forward, Snake will kiss the poster. Leaning against the poster when the door is open and knocking on the wall will either cause a "boing!" sound if knocking on the girl's breasts, or cause the enemies to go into alert if knocking on her crotch.