An unknown girl sucks my cock in the elevator and we get caught

I stood in the elevator, pressing the button for the top floor, when the doors slid shut and a stranger stepped in. She was dressed in a baggy beige sweater that hung off one shoulder, exposing a thin, green silicone wristband. Her eyes locked onto my crotch, then back up to my face. “You look tense,” she said, her voice a low purr. I smirked, adjusting my cock in my pants. She stepped closer, her breath hot on my neck. “Let me help with that,” she whispered. Her hand snaked down, rubbing the bulge in my pants. I groaned, my head falling back against the elevator wall. She unzipped my fly, pulling out my hard cock. Her mouth wrapped around the head, sucking gently before taking me deep. Her tongue swirled around the shaft, her lips tight around the base. I could feel the wetness of her mouth, the heat of her throat as she deep-throated me. The elevator dinged, and the doors started to open, but she didn’t stop. Instead, she sucked harder, her head bobbing faster. I looked up to see a security guard standing there, his eyes wide with shock. I grunted, my hips bucking as I came hard down her throat. She swallowed every drop, her eyes watering slightly. The guard stared, his mouth agape, as she pulled away, licking her lips. She winked at me, tucking my cock back into my pants before stepping out of the elevator, leaving me panting and spent.