He is most likely a member of the Russian Mafia though it is never stated nor is it said which family or bratva he belongs to. However, he is quite possibly now a member of the Petrovic Family as the strongest and only surviving bratva after the events of GTA IV and it's episodes.
However he may not be affiliated with the Russian Mafia at all and may simple be an independent Russian criminal.
- The Russian form of his name, by which he is likely called by other Russian criminals, is Foma (pronounced: Famá) making his full name Foma Francovic. It is likely he uses the anglicized version of his name to blend in better.