Eric had his own wealth at one time, and occasionally from the accounts he handled, he would skim a bit off the top, managing to siphon off a thousand or two every month without much issue.
Besides that, some people would actively give him money, or like how he dealt with Lance, he would extort money from certain businessmen.
His uncle, or as rumors suggested, his father, was the Mayor, which sometimes allowed him to act with impunity.
Only by displaying such brazenness could he live up to the rumors about his identity.
In fact, Lawyer Ossen knew everything, but acted as if he knew nothing, which further fueled Eric's arrogance.
Perhaps at first, he was uneasy, but once he realized that Lawyer Ossen didn't trouble him for his misdeeds, nor did the Mayor, his recklessness grew with indulgence.