Similarly, in the nWoD Changeling rpg you play a (formerly) normal human that has been kidnapped and taken to the Fae realm and managed to escape back to the real world. The experience has changed you somewhat, but you're still no supernatural creature (and definitely not a 'monster in a dark world').
Well...
The changelings don't strictly speaking qualify as quite human any more, physically or mentally, and what they've been through definitely
has left them supernatural through and through. However, that in itself doesn't make them "monsters", except maybe in the eyes of the kind of people who view an exotic skin colour as a lynching offence. The central themes of the game line revolve around building a new life after a traumatic stay in Faerie, and the Lost have no inherent reason to harm anyone except the Gentry and their minions. Rather, they have time-honoured traditions of protecting those that they care about from otherworldly dangers, guarding mortal dreams against fae depredations, and preventing others from being changed as they were. Changelings are basically people like anyone else (some good, some bad, most somewhere in between), but it's an explicit setting conceit that the PC types stand in for the "fairy godmothers and guardian angels" from the old tales, the "Good Neighbours" who may actually care about humanity's well-being, unlike the lords and ladies of Faerie.
In comparison with
CoC, one interesting detail about
Changeling: The Lost is that it replaces the Storytelling System's customary Morality (or equivalent) with a sanity mechanic, in the form of Clarity which measures the ability to distinguish fantasy from reality, the supernatural from the natural, and what shouldn't exist on Earth from what should. Unlike Morality, it may be reduced not so much by what the characters
do as by what they
experience, potentially under circumstances over which they have no control. For example, being fired from a job or learning about the death of a friend can threaten the mental balance... but so could even finding a demanding new job with excellent benefits or getting married after a whirlwind romance. Encountering the Gentry? The worst of shocks! And obviously, this also means that a character with low Clarity isn't necessarily a "bad person" in any way, simply... unhinged. Therapy helps.
And yes, as already mentioned earlier in the thread, the new
WoD at its heart is all about regular folks facing the unknown, not unlike
CoC.
CtL, and the other similar lines as well, is essentially an expansion set for the basic game and requires it to play. "Changeling", like "vampire" or "mage", is that expansion's featured major template which may be applied to a mortal character, either straight out of chargen or later during a campaign. But by default, all the PCs are mortal with no special powers, and a typical group might consist of, for instance, just a cop, a reporter, and a teacher.
One day I'd like to run a game based on no other setting material than that "Voice of the Angel" piece from the core book, all about the mysteries of the God-Machine disrupting everyday life and with the more nebulous "Second Children" instead of the familiar roster of WoD supernaturals.