A region Master is the Community that looks after the well-being of a region and tries to develop the region(which is the Outer Gate) to be a better place. At the same time, a Region Master that has the Authority over the Astral gate will also be able to adjust the price of using it. (Currently, The No Names did not adjust it any differently and it is still at 1 Gold to get to the other places like North Side Kouen City and South Side Underwood but they can change it to 5Gold each or something as long as it is within the price fluctuation range that is dictated by the Floor Master.) In the past, Region Masters may have been called Outer Gate Masters.(not very sure if they are the same, needs confirmation.)
The work that Izayoi is planning to undertake now to build the infrastructures of the region by expanding waterways to all the Communities in the region is part of a Region Master's task. (yes. he wants No Name to be Region Master and is doing a good job of his plan thus far...if he can survive....)