Or? Can be done with a magnet.

Load your figure.
Load a magnet on the group you want to squeeze.

=> You can add more groups if needed.

Center the magnet on the wall (or floor) in the area to be touched.
=> PhilC has very good tutorials on magnets on his site.

Make the MagZone VERY LARGE in X and Y; Say 5000
Make the MagZone only 1 to 2 deep in Z.
Put the magnet just forward of the MagBase in Z .
The MagZone should be HALF in front of the wall in Z. 

The MagZone should now be a huge circle paralell to the wall. But very small in Z, say about 1 to 2  inch.

Leave all as is.

When your figure comes close to the wall (or floor) the selected groups will come under the influence of the Magnet as she comes in the  MagZone.

And breasts will squeeze.

Takes some experimenting, but doable.

The Magnet and the MagnetZone do nothing to your figure, unless the selected groups come under the influence of the MagZone.

Att: Positioning is very sensitive, and YES, you can go too far and overrun the MagnetZone.

Poser 1, 2, 3, 4, 5, 7, P8 and PPro2010, P9 and PP2012, P10 and PP2014 Game Dev
"Do not drive faster then your angel can fly"!