(me talking like there's a snowball's chance in hell of getting any more canonmates in general)

(much less someone playing Matoriv in particular)

It would be fantastic but we know what matoriv is like

Plausible runners up with like, an upgraded snowman's chance in hell: hadlar. He sure does have a lot of interactions and feelings with both Popp and also Avan from prequel to death!

Imagine any canon point of Hadlar having to chase chickens around a small rural town

christ

Hyunkel would also be a fun option for, like, throwing himself into questing to distract himself from having his adoption recontextualized with the realization of just how young Avan was when it happened

He never thought about it before because he was six and preoccupied with thoughts of dark vengeance but yeah, Avan was only sixteen at the time, what the fuck!!!

Oh that'd be real good

Six and preoccupied with thoughts of dark vengeance is such a good description of Hyunkel's psychological profile