Once a month, she ties you, spread eagle to the bed, removes your cock cage, and brings you to full erection with her hand. Then she herself strips off, mounts you, and slides her hot, wet cunt back and forth along your shaft. As her clitoris is stimulated, she gets hotter and wetter. Moaning and shaking as she enjoys her orgasm. At no point does she let you inside her. You are desperate to cum, but there is simply insufficient stimulation to make it over the edge. Instead, you lie there fully aroused, but totally frustrated. After collapsing in a post orgasm slump, she dismounts, cleans herself up and locks you back in your cage. This is what she now calls your monthly release.
“After all, darling,” she says, “if you really needed to cum, I’m sure you would’ve done it.”