So I'm looking for guild-focused novels. Preferably on RRL. Because I have already read pretty much everything (I think) on NU. Something like guild receptionist... Please?..
I don't read from RRL so can only recommend from NU. Have you read Rebirth of the thief who roamed the world? Taming Master - less on guild but they did have guild fights
So you are not looking where the adventurers guild plays a decent sized role in the story (like MC is an adventurer doing jobs for the guild and getting hooked in their strifes), nor MC fighting magic guilds but more specifically management of the adventurers guild like The Guild’s Cheat Receptionist ?
Wandering inn has support character recepcionist in aventurer guild. Lazy Dungeon Master the same situation
Master smile... The MC is the leader of a Dark Guild. Its a story about Yandere girls with The MC but... It has what you want.