The book you recommend, The Book of Azazel by EA. Just the way that book starts is intense.
Doesn’t seem like there’s much weak about Azazel.
I would reckon more petitions, pacts and general activity on this plane should increase their power and presence, anyway — both as an individual een toy and as a gestalt of consciousnesses.
It’s not like these entities are made of coal. They don’t “run out” in the same way physical substances do.