Location: Tabor
Petitioner: Karel, Tanner
Unlocked: Begin Cloak and Dagger, reach Tabor
Reward: 100 Bloody Hides, 1 Meteorite, 25 Renown
In order to begin this side quest you first need to reach the village of Tabor, which you'll do as part of the main quest Cloak and Dagger. Meet with Jote in Clayhearth, a building on the north end of Tabor's lowest level, and two side quests will appear. One of them is Skin Trade.
The petitioner, Karel, is standing across the way from the Obelisk on the lowest level of Tabor. Karel has heard of a rare, monstrous Dread Aevis that has taken up residence nearby. He wants you to go kill it so he can transform its skin into quality product. Agree and you'll be headed off to do some monster hunting.
The Dread Aevis is waiting in the Fields of Corava, west of Tabor. Head south out of Tabor and take your first right, heading west just after you enter the Gilded Path. Stick to the main path, fighting or avoiding the enemies along the way, and you'll be in the Fields of Corava before long. The Dread Aevis is waiting in the middle of the fields, just north of the 'Fields of Corava' text on the map.
Despite its name the Dread Aevis is a standard Aevis as far as combat goes, and will not prove much of a match for Clive and company. You'll receive an Aevis Skin and a Dragon Talon for defeating the beast. Return to Karel and hand over the Aevis Skin to receive your reward.