Netflix from a friend how to remove his account to make his own?

A friend of ours has netflix, pays for it, has his account there, etc. He has the premium subscription, which can be viewed on 4 devices. I was allowed to have a profile with him. Now I want to create my own netflix account and pay myself, but somehow he can't remove me. If I were to create a netflix account with my mobile phone and connect to my television, that wouldn't work. Can someone help?

You simply have to log out of your device and then register again.