I'm planning to pour boiling water onto the sleeping cat.
That's horrible. Why would you pour boiling water onto a cat?
That cat annoys me.
That could kill or seriously injure the cat. If a cat poured boiling water on you because they found you annoying, you wouldn't like it either.
So what should I do about the cat?
Give it up for adoption. If you are thinking about harming that cat with boiling water, you need to remove it from your home immediately.