Ah

Ah was the leader of the Gigu Tribe and the adoptive father of Agu.

Background
In the past Ah adopted the hobgoblin Agu and raised him like his own child. When the forces of the Great Tomb of Nazarick began building the Monument of Ruin, it disrupted the Great Forest of Tob power balance. With this new entity inhabiting their forest, Ah presumably order the rest of his tribe to split up in order to find a new home. Unfortunately this weakened the tribe significantly, allowing the Giant of the East to easily conquer them.

Agu
Ah appears to have cared about his adopted son, however he appears to have not told Agu that he is adopted or that he is a hobogoblin.