Gahe

The Gahe is a giant-type Makamou with the features of a parrot & an ape that has long hair which covers much of its face, able to mimic the sounds in the mountain side. It was first destroyed by Echo Demon's Flame Barrage form.

Another Gahe was pursed by Bullet Demon in Episode 11. The Gahe attempted to avenge its parents, only to be wounded by the Berserk Prince & killed soon after.

Prince & Princess
They were raising a Gahe, resembling monkeys & were prone to maniacal laughter while using the fog to cover their abductions, knocking the victim unconscious & using their voices to feed it. While the Prince was destroyed by Echo Demon's Demon Fire Claw, the Princess fell to Echo Demon's Demon Fire, though their child was able to fend for itself by then.

Another pair were among the victims devoured by the Berserk Prince in episode 11.

Etymology
According to Apache legend, the Gahe, also known as the Ga'an & Gaan, are a group of mountain gods into hard rock drumming.