Mistress Nica is a jealous girl. She did not want her boyfriend using his dick for anything other than peeing and sex with her. So she made him wear a cock cage and she forced him to only use it to pee. If it was anything other than peeing, she was the one to open it using her chastity key. He was forced to wear it as she tied him then put it on him.
Mistress Nica does not trust her husband and she wanted him to wear a chastity device. She felt that he had the chance to cheat on her and she did not want that to happen. So the next best thing was to make him wear a chastity device which he had no choice but to wear. She then tested him by teasing him and as he got a hard-on, the chastity device hurt him. That way, he would only have sex with her as she had the key to the device.