Is there a good database about online where I could, for example search for "Devourers" to find out who works with Khosumet?
I'm surprised I'm the first to point this out, but Devourers don't do anything for Khosumet or vice versa. Khosumet boosts two items....
1. "Relentless" figures. (Anubian Wolves, Armoc Vipers, Dumutef Guard, Krug, Minions of Utgar, Sir Haawthorne, SuJoah, Taelord, Venoc Vipers, Venoc Warlord, and the Wolves of Badru)
2. Figures with the "Unleashed Fury" power. (currently just Anubian Wolves)
You may be thinking of the Dumutef Guard?
In which case the Devourers are....
Rechets of Bogdan
Shades of Bleakewoode