"Maybe it'll get smaller if you cum..."

"Well," you say as you glance down to the morning wood tent in your own boxers, "Usually, if you shoot your load, they get smaller afterwards."

"You want me to jerk it off?" Sam looks to you in confusion and then down to the meaty monster in her grip. She'd given you enough handjobs in the years that you'd been dating, but now, with the cock she had to jerk attached to her own body, she looks a little lost. She gives it an experimental stroke, running her fingers along the underside of the thick shaft, but her pouted pink lips stay curled in a tight frown. "It's too big for my hand."

"Then use both hands," you say. Having too big a cock had never been a problem that you'd run into yourself, but you'd seen plenty of pornos with a girl using both hands to handle an over-sized fuckstick. As Sam grips her veiny shaft with both her small hands, the sight reminds you of the dirty videos and your cock twitches in your boxers.

Your girlfriend doesn't seem to be enjoying herself as she slowly pumps her hands along her new endowment. After a couple minutes of half-hearted stroking, she looks to you in frustration. "It feels nice, but I don't feel like it's going to shoot any time soon. It's just so different than when I do it for you." She runs her fingers down to the base of her cock again and then glances up to you with big puppy-dog eyes. "Could you do it for me?"