The phrase "firehose," comes to mind, and I'm not talking length.

“It looks … like a snake,” she says admiringly, though she’s technically very wrong. It LOOKS like a normal penis, but just like you do, she knows there’s more to it than meets the eye. “How’s it bite?”

“If I put this in you,” you explain, grinding it up against her wet slit, “and I orgasm, it’s not going to stop cumming.”

“Ever?” she half-asks, half-moans as you tease her.

“Eventually. But it’s enough that I don’t know you’d be around for the end if you let me leave it inside you.” She pushes back against you at that, clearly very excited at the dangerous prospect you’re describing.

“Good!” she says breathily as the two of you continue to not-quite-fuck, grinding against each other. “I always wanted to know how much cum I could take!”

“Not scared?”

“Not even a little!” She kisses you hard after speaking, and you groan as you give in and slide your cock insider her welcoming pussy. “Oh, fuck! I’m a lot more scared of missing out than dying!” That only gets you hornier as you start to fuck her, pulling her top up over her head. You and Heather kiss as you screw her like she’s all the sex you’ve been denied by your condition, and she rides back against you like she needs this as bad as you. You carry her over to her bed and lay her down, never breaking from screwing as you lift her legs up so make sure every last inch of you gets inside her. Heather’s eyes are closed, cumming hard with a pained, eager scream a you watch her pussy gush on your hard cock.

She’s so fucking sexy, but you don’t know much longer you can last considering everything.