It's a plan!

"So you're the bratty kid sister?" Mr. Thornhaven laughs, shifting slightly, his cock still buried in you. "I could get into that. Whattya say Lisa? You into it?"

You look at Jenna, wriggling against the wall as she fondles herself, her eyes drunk and hot. She doesn't look much like your real little sister, but she's a much bigger slut. This might be fun. You stroke your hands down Mr. Thornhaven's back and give him a kiss as you rock your hips.

"Yeah, it'll be fun! Let's do it!" you giggle, looking at Jenna who grins and sidles out of the room.