Kat would quite happily have kept going indefinitely, but Mimi tugged on the chain again and brought Kat's mouth down to the strap-on. The smell there was heady, a mixture of Lucy's juices and Mimi's own arousal seeping from between her legs.
Looking up into Mimi's eyes as Jessica had trained her to do, Kat ran her tongue all over the shaft, then took the head into her mouth. Mimi smiled and put one hand on the back of Kat's head, pushing it down until she'd swallowed as much of the plastic cock as she possibly could. Just then Kat felt a movement below her -- Lucy, finally stirring, had moved between Kat's legs and was now tracing her tongue along one thigh. When Mimi released the pressure on her head, Kat eased the strap-on out of her mouth and resumed licking it, squirming as the warm tip of Lucy's tongue slid into her.
Kat saw a new look come into Mimi's face -- abruptly she stood and bent Kat forward over the chair. Gesturing toward the couch, Mimi indicated to Lucy that she was just to watch at this point; reluctantly Lucy wriggled out from between Kat's legs and took a seat.
Mimi wrapped one arm around Kat's waist and lifted her slightly, raising her ass a little higher. After planting a few small kisses on Kat's bound hands, Mimi used two fingers to spread her pussy lips and ran the tip of the strap-on up and down her opening. Soaking wet and eager, Kat's pussy practically sucked the dildo inside; Mimi stopped halfway in and reached around to tug on the chain between Kat's nipples, causing her to moan in combined pleasure and pain. Then Mimi slowly penetrated Kat the rest of the way, and just as slowly pulled back until she was almost all the way out.
Kat soon realized that she was being fucked by a true master -- or mistress, as the case might be. Mimi mixed long and short strokes, varied speeds, and sometimes stopped moving altogether, leaving Kat grinding her hips to try to get more friction. She brought Kat to the brink of orgasm several times but didn't let her go over. Lifting Kat's head and slipping a finger into her mouth, Mimi motioned to the blonde in the plaid skirt, who walked over and sat down on the big chair. (Kat never did learn this woman's name; she was known in Mimi's circle as Blondie, and she did indeed bear a more than passing resemblance to Debbie Harry.) Blondie lifted her skirt -- she was naked underneath -- and spread her legs; Mimi pushed Kat's face into her pussy.