Yes, you can remove any account from following you. There are two ways to remove someone.
Followers list: Navigate to your followers list. Find the account you’d like to remove and tap or click on the more icon {{ twtr-rte-icon:more }} to the right of the Follow button. Tap or click on Remove this follower. Confirm you want to remove the account by tapping or clicking on Remove.
Profile page: Navigate to the profile page of the account you wish to remove from following you. Tap or click on the more icon {{ twtr-rte-icon:more }} and select Remove this follower. Confirm you want to remove the account by tapping or clicking on Remove.
Please note that removing a follower will not prevent someone from requesting to follow your account (if your Tweets are private) or following your account again (if your Tweets are public).
Note: Currently the functionality to remove an account from following you is available on web only.