As Tabitha pleasured Vipress she began to feel strange. Her body felt like it was changing somehow. At first she was enjoying herself too much to stop, but soon her legs began to feel weak and she had no choice. She stopped what she was doing to Vipress and slipped away from Rick, only to collapse onto the floor. Rick went to her side.
"Honey, what's wrong?" he asked.
Tabitha rolled onto her back. "My legssss, ssssomething issss..."
She stopped, realizing how she sounded. Rick did too. Their eyes went to Tabitha's legs. Sure enough, they were drawing together, like an invisible zipper slowly being pulled down from her crotch, melding into a single appendage.
"How can I be turning into a naga ?" asked Tabitha.
Rick was shocked. "This is a very unexpected effect. Vipress was a snake and took on human characteristics; you're human taking on snake characteristics. And how were you exposed to the chemical that transformed her? Unless her body fluids are somehow contaminated with the chemical."
"It ssssseemssss the most obvious explanation" admitted Tabitha.
As the transformation progressed and feeling began to return to Tabitha's lower extremities she began to feel a very pleasurable tingle and unfulfilled desire.
"Vipress, did your change make you horny?" she asked.
"Oh yesss. That is why I attempted to mate with Rick once my transformation finished."
Tabitha looked at Rick lustily and licked her lips. As she did, her tongue stretched beyond its normal length and Tabitha realized it was becoming more snake-like. She immediately went for Rick's crotch, taking his erection in her mouth and eagerly caressing it with her new tongue. Then she slid her mouth off and lay back on the floor, an eager invitation to Rick.