Clench your teeth and keep counting.

As you watch her, you begin to want nothing more than to be in place of that ball she bounces on. Your cock could be under her as she bounced up and down. It's intense. You can hardly resist, and you can't look away--both literally and because you promised to keep count. Finally, she comes to a stop. You're so hypnotised you barely even notice until she speaks.

"Hey! I'm all done. Phew... Now I'm all sweaty. How much was that?" she asks, looking up to you.

Desperately hiding your throbbing erection behind your trousers, you breath a sigh of relief. She's finished as long last.

"Thirty. You reached thirty. Good job."

"I couldn't do one more. I'm exhausted. And if I did, my skin's so wet, my top might pop right off!" She laughs and gets up from the ball, coming to a bouncing halt in front of you. You inspect her body. Her sports bra presses so tightly against her curvy body, and her cleavage now shines with wetness. Drops lead down her midriff to her legs.

Day two. It's only day two. Five more days, and you won't have to deal with everybody finding out you're a gigantic lying fraud. All you need to do is continue to act uninterested in her beyond a friend. It's definitely not easy--much more difficult than you thought it would be. Your erection struggles behind your pants but she seems to not suspect a thing.

She sits down in the grass and pats the ground next to her. You sit down and sigh, trying to think of other things.

"Let's just enjoy the sun a bit... and then how should we spend the rest of the day? Hm."

A moment of silence falls over the both of you. Truthfully, you don't know what to say beyond just go home and rest your poor member.

"Let's cool down in the local pool! I love water!" She smiles wide.