How to make your number seem disconnected without disconnecting?

I have an iPhone and I know I can block numbers simply from my device. I know when you block a number this way they can text and call as usual but it won't go through to my phone. IIm just curious to know if there's any way I can permanently block someone so it's as if I have changed number or disconnected my phone. I don't want this certain person thinking I'm getting their calls or messages I want them to think that I don't have the number anymore at all. Is this possible? Without changing my number.

That can't be done, only way to do that is to change your number.