User blog comment:Ghmorello/Chapter 921: Rock The Dragon/@comment-7606564-20181019071538/@comment-84.215.138.20-20181019123355

Ashura Douji and Shutenmaru is the same person if you look at the shadowed version of Ashura you can see it matches Shutenmaru. So its not a wonder that he was as strong as he is. Its also explain how Kiku reacted to his name.