A metal cage

You see a thick metal looped cage around your large cock, tightly constraining it. It had a small padlock on the top, so there was nothing you could do to get out minus having the key she held. You don’t know how she put in on as you slept, and wanted to complain. After all, why did she have this device already?! How could she think a small bet could equal a whole month locked up?! But instead of complaint, you blushed and kept quite and simply say “ok Demonica, what ever you want.”

“Aww I knew you’d be my good boy, knowing to keep your girl happy. But, while you are locked up, some rules. First, it’s not Demonica, it’s Mistress or at the very least Ma’am.” You could tell she was serious, and enjoying herself, especially with the Mistress title. “Second, you’ll also be wearing a collar all month, when we go any wear, as a visual reminder you belong to me. Third, obedience will be expected as the baseline, not enough for a reward. If you want a chance to cum, you’ll need to go above and beyond. But any disobedience will be harshly punished, and you may spend much longer locked up.”

You nodded, saying “yes Mistress”. You were surprisingly turned on by this sudden **** submission and your girlfriends clear dominance. With that she said good night, mentioning she was looking forward to your performance in the morning and quickly falling asleep.

You however couldnt sleep. All of this turned you on, and the sensation of your cock straining against the cage and your inability to touch yourself just kept you awake. In the end, you maybe got an hour of very light interrupted sleep before morning.