Your girlfriend is extremely strict with your release day. Once she takes off the cage, you cannot get hard until she allows it. Even if she touches it, or gets naked, you cannot get excited. If you fail, your release is cancelled until next time..
MonMag Monthly Issue #3: What the heck is a "booru" and how can I use it to find monstergirl porn? (Now with Monty Python references and Harpy Titties!)