Eric shied away from her touch, but didn't turn around. He was unable to take his eyes off his own mother being fucked by his pet rat. "W-we can fix this...I can fix this..." he said weakly.
"There's nothing to fix," Lisa said sharply. "Even if I wanted to change back to the way I was, side effects of the Chronivac are permanent to some extent. Believe me, I know everything about how the Chronivac works now. Direct changes can be reverted -- we could probably bring your mom most of the way back, if she wasn't enjoying herself so much -- but DNA alteration means this is the new 'normal' for me. The Chronivac could change me into something else, but a reality reset would bring me back to the way I am now. If you didn't want me this way...well, you fucked up."
Eric shuddered. "Oh god...I'm sorry..."
Lisa embraced him from behind, one fuzzy arm around his neck and the other cradling his stomach. "Nothing to be sorry about, sweetie," she cooed into his ear. "I love being this way, and nothing would make me feel...mmmm, hotter than going further. You'll find out, too. It's...incredible."
Eric was lost in panic, but he didn't want to upset her by pulling away. He gulped. "What do you mean, I'll find out too? What are you planning?"
She spun him around and leaned back, gripping him by the shoulders. Silhouetted by the Chronivac monitor, her new form was still a bizarre and uncomfortable sight for Eric. Her smile grew broader on her short muzzle. "Here's the deal. I care a lot about you, you know that. We've spent so much time together. But now, Tomtom is my mate for life. I can't imagine anyone else's cock inside me. Certainly not this one --" She reached down and squeezed Eric's rubbery horsecock through his pants. Eric's eyes bulged. With her other hand, Lisa ran a claw from his Adam's apple to the tip of his chin. "So I thought of a way we can still be together..."