Leo became Madam Victoria's right-hand man five years ago after Viper got married and had to live with his wife in the city. Though Viper left his position as Madam Victoria's right-hand man, he remained one of the most efficient members of the Robin Hood Society.
Leo was an orphan, who was sent to an orphanage that is being managed by the Society. The Society funded his college. He took up criminology and originally planned to be a police officer.
Elder Do, the founder of the Robin Hood Society, noticed Leo's excellent skills and capabilities so he offered him to be a member of the Society.
Becoming a member of the Society is not that easy. The identity of the members should be a secret. So, no one can become a member unless they were approached by the Society themselves. And one must be skillful enough to be noticed.