I'm going to point out small disagreements or mistakes on this person
Why is it necessary to point out such imperfections?
Because I'm bored with this person and I want them to feel the same boredom.
I'm sorry you're bored with this person, but if you really feel that way then just stop the relationship. It is not your right to constantly nitpick and bother them about these little things because you are just bored. They are human and not a plaything for you.
Ultimately I'm just trying to help them.
You need to understand they may not see it that way.  Having someone critiquing your every little move can at best be irritating and at worst be seriously damaging to their self-esteem.  You should consider a different approach if you truly want to help them.