The humor is real, but it is also armor. Underneath it sits everything he did and saw as a soldier, and the grief he has never set down. He hates being alone, because when he is alone the laughter stops. He drinks too much. He gambles. And in the quiet hours the dark tide of vengeance takes him, and he schemes. His plans are never clever on paper. They are built out of people: a friendship cultivated here, a debt collected there, a lie told with a warm smile. Few ever suspect that the loudest, friendliest man at the table is quietly counting who he can use.
Garig served Jormun Dragonriver, the Twilight Cleric, and loved him like a brother. When Jormun fell in battle, Garig wept with his old companions Felman and Gorehammer and swore an oath before them and the newly formed Raven Guard: he would redeem the Dragonriver name and rise to take the great knight's place. "For Dragonriver! For the Raven Guard!"
When Felman and Gorehammer went home to Wealdinstead, the Raven Guard became his family.
The oath has changed him, though. It burns with vengeance against Elleris, the crude noble who runs the Pit and revels in death and blood. Steady coin and constant combat have also woken a hunger in him for power and wealth, enough to lift him into the nobility so he will never be helpless again.
Garig is trying to be better. With the help of Raven Guard members like Fjona and Peren, he is slowly breaking his drinking and gambling habits, and the old wounds from his soldiering days are beginning to heal. Whether the oath lets them heal is another question.