For the next three days, Axel didn't go anywhere else.
He diligently worked on finishing the design that he and the girls decided on.
Of course, the entire time, Wisteria's entourage was with him too, watching his every move.
After completing the river placement and wastewater sewers, he quickly constructed a water treatment plant at the far eastern end of the walls.
The design was simple, but it was different from what a standard water treatment plant should be. Instead of using chemical and physical processes to "clean" the water, it used a weird, magical technology that purified the water before releasing it back into the river.
Although Axel couldn't understand the underlying principle behind it, it was cheap and ran on mana, so it was efficient too. He just had to charge it once a week, and it could work tirelessly.
After that, the next thing he worked on was the centerpiece: the castle.
