The Concierge
A mysterious entity taking many forms but always referring to itself as a concierge, doorman, custodian, keeper, or similar titles. It has no name other than its title and when questioned as to its purpose, it describes the functions of its titles. When questioned what it is, the concierge to or for, it laughs and gives cryptic answers. It's motives are unknown, only that it seems to aid time travelers and interdimensional explorers to get back to their place of origin. Sometimes, it "helps" creatures return to their native habitat even when the help isn't wanted...