Boys will be boys

As Robin continues to strip in front of you, you're barely able to contain yourself at the impossibility of the situation in front of you. Countless thoughts race through your mind in seconds as the world seems to slow around you; Robin seemingly reaching around to unclasp her bra in slow motion.

Wanting to take full advantage of the situation, you quickly pick up the pencil and scribble your first thoughts in the rulebook, your mind quickly processing one of the countless scenarios racing through your head and modifying reality to the lucky one you pick.

Old Rule: The expression 'Boys will be boys' refers to the casual acceptance of the fact that teenaged men and young adult males have the uncontrollable urge to touch and grope the bodies of girls they find attractive.

Putting the book down, you look back up to your sister and see that in the time it took you to write your change, she'd put on the top half of her bikini, her back currently only being adorned with a light blue string, and was currently shimmying out of her jean shorts and panties.

Suddenly, you feel a sudden urge rise within you and, unable to stop yourself, you jump off the bed and rush up to your sister. You hands snake their way around her and reach up towards her chest. In your waste, despite waiting to slid your hands under her top, you instead push the entire bikini upwards, forcing it over her tits and causing the newly naked flesh to bounce into your waiting palms.

The moment Robin squeals at your touch, you're suddenly brought back to reality and wonder what the hell came over you. Worried that your sister will castrate you for what you've done, you're just about to take your hands off of Robin's glorious tits when instead, she surprises you by bringing her hands to yours, pushing them tighter on her chest as she chuckles.

"I should've known you wouldn't be able to keep your hands off." She said between breaths, "Should've changed in the washroom."

"Sorry." You mumble, a strange mix of shame and excitement as the present situation coursing through you.

Your apology just brings out another chuckle from your sister. "No need to apologize. I'm well aware of men and their urges. Just touch me as much as you need and then we'll go back to being regular siblings again."

You groan at the casualness of her tone, squeezing her boobs as you push her towards you. The action causes her to squeal once more, and you feel her nipples harden a little in your grip. You glance down over her shoulder, catching a glimpse of her naked abdomen and legs, her shorts and panties discarded uselessly around her ankles, and feel that urge come back once more with ****.

This time, its just your hand that moves on its own accord, letting go of the heaven of flesh it was currently holding and instead making its way between your sister's legs. Robin, understanding where your hand is going, slowly parts her legs to allow you more room and welcomes your touch as you gently cup her mound. Your fingers snake their way through soft hairs and over moist lips before gently rubbing the wetness that is your sister's pussy.

"You're wet." You exclaim, both curious and intrigued that your touch could be turning Robin on.

You both feel as well as hear the warmth radiating from her blush as she speaks. "Well, what girl wouldn't get hot and bothered knowing the men in her life find her so attractive they can't keep their hands off her. It's flattering."

You stand there silent, letting your hands roam and familiarize themselves with Robin's body. Your sister doesn't say much else, letting you explore her to your leisure. You don't miss the fact that her breathing became shallower and that her blush, which had started on her rosy cheeks, had extended and flushed most of her chest into a light red.

"Michael!" A voice booms from the threshold of the bedroom, "Get your hands off your sister and let her pack!"

Both you and Robin jump, turning to see your mother standing at the entrance of your newly shared room, hands on her hips, a stern look adorning her face. "I told you we're leaving within the hour. And, I see you haven't put anything inside your suitcase yet!"

"Sorry mom!" You exclaim as you rush away from your sister, Robin standing where she was as she readjusts her bikini top so that it once again covers her tits. You grab the suitcase as you run by it, stopping before your dresser, pulling the top drawer open. "I just... lost control." You sheepishly admit, not really knowing what to say.

Glancing back towards your mother, you watch as she shakes her head, all worries of her punishing you for groping your sister vanishing from your mind as you watch her casual response. Across the room, Robin has finished putting on her new bikini, and is also in the process of finishing what's left of her packing, shoving random articles of clothing inside her own suitcase.

You hear your mother sigh as she exits the room. "Boys will be boys..." She mumbles to herself as she head further down the hallway, leaving you and Robin to your packing.