In the Cleavage You Go Alice! Alice & Roxie in: GYM RAT chapter 3 by Marak077

There's a special kind of pressure you could only get when a giantess stretches her whole body, squeezing her cleavage together with her tiny mouse girlfriend between them that as they press each other squeeze the joints and massage the body two-for-one. Alice felt herself pleasured and exhilirated, sure it was a little painful but it just pull herself just right she drooled a little, and Roxie could feel her little mousegirl enjoys this.

"Hmm, if you really like it that much... You'll love the treadmill." 

Taking her steps to feel Alice bobbing around her cleavage, she steps up the large treadmil, grab the remote for it and set it up to... Well, how about... 25 km/h?

It gradually increase to that particular speed, because Roxie knew 25 was a hotspot for her sweating droplets, waiting for it to pool to do a little breathplay while Alice was cooking near the slowly rising heartbeat of her skunk gf. More and more her cleavage jiggles and sways smashing onto her and each other. 

However, neither one expect that when Roxie nearly lost her footing and tried huffing her chest, the sudden slinging motion unfortunately threw Alice up in the sky like a trebuchet which Roxie was unaware off at the time, she would almost hit the ceiling thanks to the slippery sweat reducing friction, had it not been for the fan Alice manages to catch. Bad news was, the fan's force was too powerful for her to hang, and even the catch requires a certain level of force to reduce the catches own friction, so inevetably she falls just near...