Breasts (of holding)

"Everything for sale, ask for prices" is now clearly written above the cute cashiers cleavage.

"Oh," she says, looking a little startled, "I guess I'm for sale now." She takes a moment to think. "...It's not like anyone could afford me, though."

You grin at her. "How much for just your breasts, then?"

She looks like she's about to answer immediately, but then she suddenly stops, a shocked look flowing over her face. "F-for you? Th-that would be... Um, n-nothing..."

"Well, in that case, I think I'll take them," you respond before diving in and playing with the stammering woman's tits. They're deceptively large; the cashier is wearing a jumper and underneath she's fairly slim with disproportionately large assets. Your hand slides down her flat belly, and--

"Hey!" You feel a sting as you're slapped away. "Hands off."

"Heh, right. Sorry," you chuckle, returning to 'your' breasts. She looks a bit peeved, but nods.

Your mind wanders a little as you're lost in your new breasts, and soon you have another idea.

Grabbing your pen and pulling her jumper down again, you spread your breasts apart and write between them:

Cleavage of Holding

Once you're finished, she cranes her neck to read the words upside down. "Holding? What's that supposed to mean?"

Quickly fixing the woman's clothing, you look around the store for the biggest items.

"It's a Dungeons and Dragons reference," you explain, grabbing an armful of poster tubes. "And if this works like in the game..."

Getting excited, you pick out one of the three-foot-long tubes and start to slowly press it into 'your' cleavage. It pushes the cashier's breasts apart and slowly slides into her jumper, looking normal at first... But soon it becomes clear that more is disappearing within than would ordinarily be possible. It doesn't take long before the entire tube has disappeared without a trace.

Once the first experiment is done, you play around for a bit; pushing things in, pulling them out, faster, slower, from the bottom, from the top. When reaching in you always seem to retrieve the item you want, and it feels amazing. When you pull the breasts apart there's nothing but a valley of skin, but when pushed together as cleavage it becomes a magical bottomless container once again.