"Heh. One night in a "haunted house"? I'm not silly enough to believe in ghosts. This bet is as good as won.
As the woman sits down on some dusty cushions, a sudden chill passes through her breasts.
"Brr, it's kind of chilly in here. Maybe I should have worn more layers", she says as she looks down at her thin top, straining against her freshly expanded tits.
"Huh? What happened? Have my tits always been this big? I don't think so..."
Suddenly, another chill washes over her breasts, and another.
This time she feels the growth as her tits gurgle and groan, tearing her top to shreds.
"Oh my god! What's going on?! There's no way something like this could happen naturally. That strange chill I felt...this has to be...GHOSTS!"
Warm milk explodes out of her swollen nipples at the realization.
"Fuuuck, forget the bet, I should go while I still can!"
She goes to stand, but it's too late. Wave after wave of ghostly chill assaults her breasts.
"Aaah! There's just no way! I'm sorry! Ghosts are real, please just make it stop! I call off the bet! Just get me out of here!"
No one heard her cries for help. Her friends had left her there alone in hopes of scaring the cocky smirk off her face.
It looks like she will win the bet, whether she likes it or not. Trapped under the mountainous fleshy mounds that her breasts have become, she has become a prisoner at the mercy of the ghosts of house.