Yes... for now

You hesitate before giving your answer. "Yeah, I guess that would be okay, but only..."

"Great!" Gwen leaps out of her chair, clearly very excited at the prospect of playing spy. "I'll just have to pop home really quick to pick up a few things, though, and to make excuses for the parents. Don't go anywhere until I get back!" She's out the door before you get a chance to respond. You would get up and chase after her, but Allison is still sitting in your lap.

Speaking of Allison. "John, why did you just invite your sister along for our date?!" She emphasizes her words by pressing her index finger into your chest. That's something she's always done when she was angry with you, and while you would never admit it to her, you've always found it kind of cute. This time, though, it's hard to appreciate her cuteness while she's poking your boob - it turns out that hurts a bit more than you would have thought. You cringe as you try to explain yourself: "It's not like she would have taken no for an answer. Besides, I'm sure she'll leave as soon as she realizes what she's gotten herself into. It's not like she's going to want to watch us make out - I'm still her brother. Now can you please stop poking my tit?"

It seems to take a moment for Allison to understand the question, after which she recoils as if she'd burned herself, screaming "OhMyGoshI'mSoSorry!" The sudden motion turns out to be too much, and the chair tips, sending both of you sprawling onto the floor. Allison lands on top of you. There's a silent pause for a few moments as you look at each other stunned. Then Allison starts laughing, and you can't help but laugh with her. The two of you must look quite ridiculous.

As you both recover, you ask your girlfriend "um... can you get off of me now? I can't move." She's about to get up when she stops and flashes you a devilish grin. Uh-oh. As she repositions herself to straddle your hips, you ask: