Let Alex decide

You figure you may as well enjoy this to its fullest and let Alex enjoy it however he likes, too. You let go of your worry, and let the pleasure wash over you. Instead of telling Alex where to cum, you just push your hips back at him in time with his thrusts to maximize the penetration.

Not even a minute later, you feel Alex's dick harden and thicken within you and hands squeeze your hips hard. You wonder whether Alex will leave it in or take it out. A quick flash of fear and excitement washes over you as you question whether the condom is still intact. Before you can do or say anything, you feel an emptiness as Alex pulls himself from you and you immediately feel a hot splash of cum spray from your asshole all the way up your back. A second rope stripes your left butt cheek, and a third follows suit. The remaining seed dribbles from Alex's dick onto the backs of your calves, running quickly down to the bedding beneath them.

You hear Alex sigh contentedly as you turn your head to look at the mess he's made of your backside. You reach back and tentatively play with the thick substance on your ass, marveling that even a single drop of the substance could find you pregnant and stuck as a girl forever.

You suddenly feel the line covering your pucker begin to liquify, dribbling down toward your labia. You freeze in a panic, unsure of what to do to stop the slow march toward your impregnation. Thinking quickly, you fall onto your side, grab a fistful of the bedspread and begin wiping away Alex's sperm.

"Aww, seriously!?" he exclaims, "Is that really necessary?"

You pause wiping for a moment and scowl at him. "I don't want to get pregnant," you return to wiping, "and your cum was waaaay too close to going inside me."

"Fuck! Fine, but you're washing the sheets."

When you're satisfied that you've wiped enough away, you stand up to go to the bathroom to wash up. Your right foot lands on a condom wrapper. You pick your foot up, the foil clinging to it. You grab it and find that it's unopened and has a perfectly good condom inside.