Kayla had to work harder and harder to stay aboard as the centaur's gait started to become uneven. Then Lily grabbed hold of the stuffed centaur toy's legs and forced her head downward, roughly thrusting herself onto the rubber dildo.
"Hnyyaaaa!" cried out Fey, her back hips bucking up into the air and sending her rigid throbbing cock dancing up and down. Kayla was bounced fully airborne for a moment before crashing back down. She stumbled forward across Fey's back and landed atop her sister inadvertently ramming the otterkin girl down to the base of the rubber dildo with a muffled cry of alarm, her throat distending in the shape of it.
"She's so tiiigght!" wailed Fey as Ellaria desperately helped keep the centaur up as she stumbled from hoof to hoof, overwhelmed with the sensation encompassing her length.
Kayla realised she was holding her sister down and scrambled up. Lily came with her, her lips dragging behind her mouth in a long wet schlurping suck, leaving the purple rubber shiny with saliva in its wake. Her head came up and the head of the dildo popped from her reddened lips with a spatter of spit, the heavy floppy rubber arcing down in her hands as the otterkin drew in deep heaving breaths, strings of saliva connecting her stretched lips.
"That, that was a bit deeper than I expected," she breathed.
"You gotta show me how to do that some time," said Kayla.
She put a hand on the dildo, which was bending down with its own weight, and hefted it back. The two sisters glanced at each other, all four of their hands helping to hold the heavy rubber length up. Kayla began first, her hands slipping over the rubber which was slick with Lily's saliva. She couldn't help herself, she wanted to get more reactions from Fey, and she got them, the centaur whimpering under her touch being transmitted through Lily's power, their small hands feeling like much larger hands on the centaur's length due to the relative size difference between the dildo and Fey's actual penis.
The otterkins' hands rolled up and down the floppy length, the rubber wobbling back and forth as their hands pressured and pushed and squeezed, pulling at the length, giving it an enthusiastic two person hand job.
"Oh, oh gods, g-girls I'm about to- to-!"
Kayla's and Lily's motions became furious, their hands jerking up and down the length sending it flailing in their grasp. Fey groaned and gasped under their ministrations, her hips whipping back and forth until she suddenly froze up, her body stiffening and her back arcing.
Fey unthinkingly grabbed hold of the red-headed elf at her side and clutched her close, smooshing her face against her bare upper abdomen to the elf's shock. Ellaria struggled for a moment then relaxed into her as she felt Fey's warm body against her head, pressed up against the immense physical power of the centaur, her body trembling and jerking as she reached an incredible peak, Ellaria could literally feel the tense clenching up of the centaur's body as she came.
Fey's dick became more rigid than ever, battering up against her barrel roughly as it surged in girth and the head flared wide, semen exploding down its length in massive roping surges, once, twice, three times, four, she came and came and came, blasting her prodigious unending virility over and over into the Dimensional Bag ejaculating thick glue-like white into its hidden depths.
Fey groaned and gasped, barely holding herself together, practically leaning on Ellaria who stumbled desperately under the centaur's immense weight.
"Oh g-gaawwwdddd!"
The centaur's hips continued to buck, her throbbing ejaculating cock waving madly as more and more of herself streamed outward and into the bag.
It was as she was spurting for the ninth time that she felt something different, wetness around the tip of her dick. This was different from Lily's ability, it felt much more direct and as another powerful rope of cum forced its way inside the wetness washed over her length and she realised what was happening. The sound of fluid spattering against the ground filled the air confirming her fears.
"Oh no, it's overflowing!" Shouted Kayla leaning over the side of Fey's barrel. By this point the centaur's unusual movements were starting to draw eyes from the other caravaneers around them.
Kayla was correct of course, the Dimensional Bag on Fey's cock head was round and taut, seeming somehow overly full. Cum was washing from around Fey's dick in greater and greater amounts as the bag overloaded with Fey's increasingly powerful ejaculations.
"I- I can't stop!" groaned the centaur trying to clamp down on her groin muscles, performing desperate kegels but utterly failing to stop the flow, in fact, it only seemed to make her ejaculations grow all the greater.