If someone is following you on twitter and you don't want them following your account but you don't want to block them either, here is the secret sauce to bump them off your twitter followers list:
1) Go to their account
2) Hit block account
3) Hit Unblock account
4) Account is now off your followers list but not blocked from your account.
**It basically makes it so you don't show in their twitter feed but they don't realize you have erased yourself from their list of accounts followed.