I had an awkward moment with my dad, which he just comes in my room without knocking and sees me watching this and then, I turn around and he's standing there and he just's walks out like nothing happened.
Have you ever tried putting a sign onto your door saying "Knock and I shall be there in 5* seconds or less, if not, I am not there and you may enter." *Time doesn't matter, 5 is just example.
