Pokemon Dr. Otaki's brother

Dr Damu has no younger brother, only a cousin, Ye Cheng? Damu Ye Cheng? Big wood first appeared on the sun/moon. When the protagonist arrives in Marie, urala Island, Rotom will recognize him first. Big Wood and Ye Cheng say hello to each other? Dameihui told the protagonist that Lotom's picture book was invented by the inventor teenager in Carlos area, and told the protagonist that he was doing research on regional morphology. Finally, he hopes that the hero can take good care of Rotom and go to Mariel Library to find him. When the protagonist goes to the Mariel Library, he will give the protagonist a general introduction to the regional form, hoping that the protagonist will show him a top cat that looks like arora. After completing the task, the protagonist will explain why top cat will mutate in arora, and then give the protagonist a sweet ball. Ye Cheng? Damu will also introduce his cousin, Dr. Damu, and mention to the protagonist that Dr. Damu's grandson will visit arora.