A chastity tube

She comes back to the dorm, and acts all sneaky. She points the gun, and quickly has you with your hands and legs cuffed, sitting on the edge of the bed naked. Shakily, she reaches until her bag and pulls out what looks like a mold for a cock and balls.

She turns to you, "So as you probably know, I can't keep you here forever." she says quietly.
"I'd like to, I really would, and I know you would like to stay, but people would start asking questions."
"Now here's what's going to happen. I'm going to let you out, to go about your normal life, classes, friends, etc.
But there's a few ground rules we have to establish. First, you're going to break up with Chloe. She probably has been wondering where you've been. Break the bad news to her, tell her you're through. Then, you're not going to tell anyone about 'us'. At least not yet, not til I decide. And finally, of course, you'll come back here every night, otherwise you would just miss me way too much "

"Why would you do this you say? Because, if you ever want to cum again... ever want that precious release, you're going to follow every word. every command. everything I fucking say babyy." She licks your ear, sending chills down your spine.

She walks up to you and snaps shut the chastity tube around your cock and balls. It keeps your penis nice and curved, impossible to get an erection, let alone cum. She puts the key on a necklace that dangles down her shirt, resting on her small breasts.

"Now, then, do you have any questions?"