Wang Li Lei's relationship with the head of mafia was as to how Wang Li Lei called him "Shifu".
After his parent's death, Wang Li Lei was targeted by many people especially his evil uncle who wanted to covet everything including Wang's company and the position as the heir of Wang Family.
However, that wasn't the reason as to why Wang Li Lei bear much hatred to his own uncle. It all started when Wang Li Lei heard the truth about his parent's death from his own uncle's mouth.
His uncle clearly said. "Killing them wasn't enough, I should have killed their child too-"
Wang Li Lei was 12 years old when he knew the truth. Anger and rage-filled his heart, but at that age, he couldn't do anything much less giving a straight punch to his uncle. Not soon after, because Wang Li Lei was underage, his uncle took the place as Wang's new CEO and the next heir.