My Tattooed GF Grinding Her Ass on My Hard Cock

She knows exactly what she's doing to you. Her hips are moving, slowly grinding against you. Her ass is flexing, shifting with each motion. You feel the heat, the wetness. Your pulse is racing, your breath catching.

Her black bra is still on, but it's all about what's underneath. Her long black hair cascades down her back, over the tattoo. You see glimpses of penetration, but it's mostly hidden by her curvy ass. A hand reaches up, touches her hip, her thigh. She keeps moving, keeps grinding. The motion is relentless, the rhythm building. You're getting hard, feeling the ache grow.

The grinding continues, the motion steady. You're stroking along, feeling yourself edge closer. Your hand is moving faster now, matching her rhythm. You're not going to last much longer. The tension is building, the release imminent. But for now, she just keeps grinding, her ass flexing with each motion. What happens next?