I've thought of a little challenge for the slave - I'll sit down on his face and smother him under my ass - and stop the time how long he can last! And obviously I don't want to make it too easy for him and therefore I put on my tight hard jeans for this test. My ass flattens his nose and completely prevents him from breathing when I sit down on his face with my full weight - and then we'll try to increase the time! To be a comfortable seat for his mistress, he'll have to endure longer than just 30 seconds ... and I'll train him to hold his breath way longer! I don't care how much he struggles, whines and begs ... he'll endure it as long as I want to!