Expansive Discharge - Butt Expansion Commission (Patreon)

After a particularly rough training skirmish, Mercy noticed that her staff was making a grating sound. Probably just sand in the bearings from the Oasis air, and she thought she'd fix it herself. After all, Brigitte was all the way back in Switzerland and they had another training session in the morning. Screwdriver in hand, she pried at the safety latch, but in her haste forgot to disconnect the healing cell. When she snapped the cell out of its alignment, the cell discharged all its energy into the nearest targets, notably Mercy and her bunkmate Tracer. 

The unregulated regenerative energy surged from the breached cell, flooding their bodies with a somewhat pleasant warmth. Within seconds, Mercy felt her body begin to swell as the energy congregated to her rear and thighs. Her ass swelled with each surge from the quickly draining cell, her leggings straining to contain her growing heft. With a loud rip, her leggings split, allowing her body to grow unrestrained. Her ass thudded on the bed with a clap, the bountiful flesh jiggling like gelatin. She strained to look at her new body, but a moan from Tracer caught her attention. The Brit was kneeling with her ass up and head buried in the mattress, her lip quivering as she struggled to compose herself, but as the next surge filled her body she couldn't help but gasp as her ass filled her leggings. Her swollen thighs and hips drew the elastic fabric tight, and the next surge was enough to shred the stricken fabric. With a heavy slap, Tracer's hefty ass landed on the bed, the springs groaning under the weight. Tracer glanced over her shoulder at the plethora of flesh tacked on to her hips, and with a devious smile looked to her startled teammate. Neither Tracer nor Mercy showed up for training the next morning, but their hotel room had garnered multiple noise complaints. 

This animation was commissioned by The King of Booty! I almost feel like it's cheating to keep using Tracer for ass expansion, her butt's already big as is. But in the wise words of every expansion lover, "Bigger is Better". At least she has a friend this time to share in the fun! 

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