The city name is Nagate. It is always changing, the routes won't get you from A to B without magic travel permit. But you can't change shit. Is it pure magic or is it science what we can't understand?
The story has begun when someone bought an antiquities, the seal breaker and finished when someone used it and they wound back in time. The story start again but the second time another protagonist get the seal breaker. Nothing are the same but the begining and the end. We get four full circles. What is it? Is a mistake in the system? Is someone trying to achieve a goal? I won't tell.