Of course. The old concave-convex world can be seen on Mile Mile. "Old design of concave-convex world" refers to the old design of the animation "concave-convex world" broadcast on 20 17. These old settings include character design and plot background. In these settings, we can learn the stories and backgrounds of the protagonists, the relationships and conflicts between the characters, and the wonders and mysteries of the whole "concave-convex world".