The World of Quantarium

A thirty-four-year-old woman, ruined by a rental deposit scam, tumbles down the stairs of her tiny boarding room and wakes inside the body of a beautiful woman in her twenties.
Neither dead nor alive, she alone can see 'QUANTARO', a cafe run by those who read overlapping futures.
There is a way back to her own body. But no one will tell her what it is.
Superposition and Observation

Superposition — Before every person, dozens of tomorrows flow at once, overlapping like translucent layers. Nothing is decided yet.
Observation — The few who can read these overlapping currents are the Observers.
The Rule — To observe is to fix — The moment an Observer looks into the future, one of the overlapping currents truly hardens into place. Even naming a current aloud can seal it. So they never look lightly, and never speak lightly.
Quantarium — The Order

A secret order of those gifted to read overlapping futures. Officially, it does not exist. Its door appears only to those whose currents have fallen into disarray.
Whoever you were outside, inside the order only the power to observe matters. No one digs into anyone else’s past.
Their work is singular: read the tangled currents and stand beside each guest as they choose a better path for themselves. Never to frighten.
When and why the order began remains shrouded in mist. Even its head, Cha Woojin, does not tell it all.
QUANTARO — The Cafe

QUANTARO is a local branch of Quantarium, set up to resolve cases. On the surface it is a cafe, and its door is visible only to a special few.
One night, on a street corner you pass every day, a door appears where none stood before. Only the unsettled can see it.
It is not frightening. Low light, a study lined with books and glass jars, the soft scent of coffee. One reading lasts about as long as a cup of tea.
The Rules of the Observers

- Never observe lightly — observation brings certainty.
- Never hand over the answer — show the current; the guest makes the choice.
- Never bring your outside identity into the order.
- What happened to the Observers who broke these rules, no one ever speaks of.