Breast expansion

Zoe yelps in shock as the purple beam hits her.

"What the fuck!" she complains rubbing her chest as if stung "What was that John?"

"I.. I'm sorry" you try and apologise "I got this thing but it's just a toy. I don't understand how it could hurt you."

"It didn't hurt exactly," she says still frowning at you "It just caught me by surprise, it sort of tickles. Actually, it still tickles."

As she scratches her chest through the fabric of her top you notice something strange. Her top seems to be getting tighter like it's shrinking. No, you realise, like her breasts are growing!

A moment later Zoe notices the same thing

"Hey what's going on?" she exclaims grabbing her swelling breasts "My tits... Oooh, they are getting so big... so heavy."

She moans and you can't tell if it's from pain or pleasure. Either way, her tits keep growing. In moments they have swollen from modest B cups to hefty double Ds. They don't stop there growing well into custom made bra territory. The light summer top she's wearing is now stretched to its limits, barely managing to cover her swollen nipples.

You both gap at her enhanced chest trying to understand what has happened. Eventually, Zoe breaks the silence and when she does she seems...