A Young Voyeur's Pervy Adventures/Day1/No, leaver her top alone
There's no way she's actually daring you to undo her top, and if that's the case then the last thing you want is to destroy her trust in you. You release the knot and lower you hands down her back. Wanda gave you a glowing smile.
"I'm proud of you Matt. I thought for sure you would take the bait, but no, you retained yourself. Just like when you refrained from undoing my bottoms."
Before you could speak she interrupted you.
"I knew what I was doing sticking my butt out like that. Like I said I am very proud of you for holding back. Especially after how exited you got with spying on Penny and, well, now."
She finished with a quick glance downwards, clearly referencing your erection. You finally decide to relinquish your grip and put a little space between you two. When you did so Wanda took your face in her hands and gave you a peck on the cheek.
"I'll give you a little reward for your restraint later, okay?" She winked. "Now come on, let's swim a little!"
She turned, her hip brushing past your erection in the process. Given all she said you're positive it was intentional, but you choose instead to ignore it and have some good, honest fun with your sister. The two of you laugh and splash and have a good time. Your erection stayed for a little bit but you avoided any close contact until it went down, something you know Wanda appreciated.
What happens next?