It is that time of year again to lock away those troublesome dicks for a month of peace and quiet. If you don't have a chastity cage for your Koikatsu characters, here's the popular Short model from FutaLab you can use for your own Chara Studio scenes.
To use, import into your scene and attach to the character. I prefer the penis slot but you can use either the vagina or the anus if that's easier for you.
The balls are physics enabled, so they'll flop around as you move the cage back and forth. I've added a dynamic bone collider to help keep the balls from clipping through the cage. Keep in mind that this collider will also interact with any other dynamic bones you have in the scene.
You can adjust the color of the peen by opening up the Chastity Cage folder and modifying the SOS Cock prop inside. Easiest way is to modify the colors using the Anim control. But for accurate color matching, you will want to use Material Editor to switch over to the Skin shader and provide your own main texture.
The cage itself is made up of primitive objects. You can select them all and use the Anim panel to recolor the cage to suit your tastes. You can even try swapping over to using the Goo shader for a transparent plastic look. Just be sure to increase the Render Queue value to 2500 so it draws after the peen and blends properly.