Henry studied his stepsister, taking in the hard nipples on her C-cup breasts, her flat stomach, and her shaved crotch. Their parents had been married for ten years, and he'd never noticed how hot Kirstin was until a few hours earlier.
Kirstin winked at him. "What are you looking at?"
"One of the hottest bodies I've ever fucked," Henry replied.
Giggling, Kirstin struck a pose, one hand behind her head, the other on a thrust-out hip. "You really think this body's hot?"
"Hell yeah." Henry went over to her and covered her tits with his hands. "Very, very hot. Especially after that fuck. Oh, my god, I thought you were going to fuck me to death!"
"You started it." Kirstin reached down and fondled his half-hard cock, bringing it rapidly to full hardness. "You're the one who fucked me with my dildo."
"You're the one who was fucking yourself on the couch when I came in," Henry countered. "Beautiful woman fucking herself with a piece of rubber, what was I supposed to do? I couldn't let you suffer."
"Sure you couldn't. You just didn't know what else to do with this hard-on."
Kirstin knelt and took Henry's dick in her mouth, engulfing the head and sucking hard. Henry shuddered; his little stepsister was damn good at sucking! "That's good, baby," he said. "Keep sucking my cock. I'm going to cum right down your throat."
Kirstin released his cock and looked up with a grin. "No, you're not. You're going to cum all over my tits."
Fuck! Just the words were enough to almost make Henry do just that. Never mind the image that leaped into his mind. Kirstin winked again and licked his shaft, then resumed sucking as much of his thickness as she could fit in her mouth.
Henry looked down at her, loving the sight of Kirstin's blonde head bobbing on his cock, and sent up a silent thanks to their parents for asking him to house sit while they were away. He'd resented the chore until the moment he saw Kirstin on the couch with the dildo in her cunt. Now he hoped their parents would decide to prolong their trip.
As she sucked, Kirstin gripped the base of his shaft in one hand and fondled his balls with the other. "Fuck, yes!" Henry exclaimed. "Damn, Kirstin, I'm going to cum!"
Kirstin stopped sucking and aimed his cock at her tits. She jerked him hard and fast until he shot his load across her chest. Then she scooped some of his cum up with a finger and stuck it in her mouth. "Yummy!"
"You're one hot little slut, you know that?" Henry helped her to her feet. "Want something to wipe that off with?"