You should be able to accept or deny someone who wants to follow you.
There is somewhat of a way to do this, actually; if you have an account blocked, the user can no longer follow your account.
Accept/Deny is more of an "OPT-IN" method. Currently, we have post-facto blocking, which is an "OPT-OUT" method.
so I'm new to this site, I didn't even know you are allowed to follow people... I'm still clueless but thanks for the heads up