Probably a Scam
Review about NaughtyMatureFlirtsStarted using naughtymatureflirts.com as some of the women look like the kind of girls you'd like to meet.
But then you discover:
*) You cannot communicate with these girls unless you pay for "credits"
*) Girls who are supposedly English girls speak English like it's not their first language
*) If you push them to send a photo that proves they are real (e.g holding today's newspapers open at the 5th page) they'll just send you a library photo of themselves naked
*) Their Terms & Conditions give them the right to make up profiles and send false messages:
3.9 Festivus Media BV explicitly reserves the right to create profiles on the Platform and to send messages to the User on behalf of these accounts. By accepting these Conditions of Use, the User understands and accepts that some of the profiles on the Platform are therefore fictitious and they have been created only to exchange Messages with; real-life meetings are not possible for such Accounts.
*) They are based in Holland and your money is going offshore
Maybe some of the profiles are real - but they won't be those of the good looking girls you have as Favourites.
Avoid!
Cons
They make up profiles and message you pretending to be these girls!