Stonehead

This NPC is located at the gate of the ember ward, and is the objective of the achievement Best Buds With Benefits. Beside him is a Chewed Light Shard that starts the quest Snacks for Stonehead. To make the quest object interactable and get close enough to pick it up you must pick up the Hollow Rock behind him, just to the left of the gate on the inside of the Ember Ward.

Snacks for Stonehead requires you to gather some various materials across the Ember Ward-
Gooey Bug Bites from the nearby Ravenous Swarms,
Ash Crisps from Ash Crawlers,
Mirror Candy from mobs at the Shrouded Asylum
and 'A Light Snack', which you can get by picking up a Remnant of Light.
To complete the quest run up to him without the Hollow Rock disguise and allow him to pick you up, at which point you can talk to him to turn it in.

Best Buds With Benefits is awarded on completion of the quest and your character gains the buff Stonehead's Best Bud Benefits, which allows free passage past him.

The hollowed rock to get the quest next to him is at 38.86 64.31, it’s very well hidden amongst the other things it’s next to

The rock you need to click in order to interact with the quest object near Stonehead (the exclamation mark) is hidden in plain sight. It is on the left side of the gate if you are looking at the gate from inside The Ember Ward, approximately 20 feet away from the quest object.