Explain me about gamesharing ps3?

I recently gameshare a person for minecraft i downloaded it and worked fine. The person with whom i gameshare changed his password also so if i delete the user in which the user id and password is(which is changed) will it effect my game. And also if i do the same thing in future do i have to have the users… It look too messed up…

If you delete the user you will lose the game. You don't have to sign in with the new password if you already downloaded the game though.