A huge mare, at least twice the size of Rainbow Dash the little chair, starts backing up, ass first, towards Dash. Her tail bounces from side to side as she closes in. From this angle, Dashy gets a good look at her rear end. Her ass is absolutely huge, not just compared to Dash, but even for her own impressive size. It looks more like two gigantic moons rubbing together. Ripples run up her voluptuous cheeks and they get bigger with every step she takes. She glances back and lines her sizeable rump up with the seat.
 
Dashy stares up at her impending doom as it hovers over her. The huge mare’s rear blocks out the light from above and casts a shadow over her like an eclipse. The mare lifts up her tail and hastily swings it around her thigh. Her flank squeezes in between the armrests as she goes down. Then, she slams her ass down on Dash’s padded face, her huge cheeks spread across it until it disappears from view. Her full weight bears down on Dashy’s face and smothers it under two, plump orbs of mare flesh. Dash’s whole face molds around the mare’s fatty cheeks to form an impressive ass groove. Her nose pokes up between the cheeks, poking the tail hole. The sharp smell of plot is quickly thrust down her nose and makes it burn.
 
The air beneath the mare’s huge thighs gets warmer and smellier as it wafts down to Dash’s face, clinging to it and leaving her own unique mark. Sweat begins to form inside the mare’s dark deep crack. Tiny droplets run down her inner cheeks to be absorbed into Dash’s cushiony face. “Ugh! It stinks so much!” The mare rubs her fat ass into the chair. She spreads her butt cheeks along Dash’s face even further. She forces her flank down and rubs her tail hole along it. She sighs deeply as she feels Dashy’s nose run along her crack and scratch at her most sensitive parts. Dash is completely cut off from the world outside of Starlight’s gigantic rear. Trapped under her stinking, sweaty plot.