Some thoughts on what would be required.
Castration would have to be the focus.
The cat-like domme would have to be hunting a mousey sub-male with the intent to trap and castrate him.
The Mousey sub-male would have to be aware of such predatory dommes and what they intend to do if they catch him and which he wishes very much to avoid.
The domme would begin by catching the sub-male and then get ready to castrate when he would ‘accidently’ be allowed to escape at the last minute. Of course the escape would have been planned by the domme so that the sub-male would quickly fall into another trap. The threatened-castration/escape/recapture cycle would be repeated with the sub-male becoming increasingly frantic.
Two possible endings: 1) the sub-male becomes exhausted and realizes that castration is really what’s best for him and he gratefully submits, or 2) the domme tires of the game and could care less how he feels about it and just castrates him. Another variation would be for the domme to promise the sub-male that if he can escape one more time she will let him go but then just as he thinks he has finally escaped her clutches she traps and castrates him.
She holds his severed scrotum and testicles aloft in triumph grinning ear to ear and laughing a full, deep-throated laugh.
He cries piteously in his squeaky little mousey voice as the domme’s assistants work to stop the bleeding and close the wound.