Mark, eager to explore his anal limits, retrieves his wife's large buttplug from their bedroom drawer. Kneeling on the floor, he admires the size and texture, his heart pounding with anticipation. He teases his asshole with his fingers, lubing them up before gently pushing the toy inside. Gasping at the initial stretch, he relaxes and begins to thrust, his big cock hardening at the sensation. He masturbates with one hand, the other keeping the plug firmly in place, his feet flexing with each movement. His moans fill the room as he trains his asshole, desperate for more.