Riku Hirota. It was the man who vanished into the Earth after he awakened his Gene and was brought to the place where you could see the lowly monster inhabited in the ordinary place like a vast forest.
_
To begin with, Arisu and Riku headed to the Arzotoc's library. To gather some information where they could find the materials for the pipeline they were building. Remember, the crops of this village have to lack water, so in no time, the supplies of their food would surely be short.
Moreover, for Riku, it wasn't his main reason why he was doing this thing. He was looking for any magical book that could help him to summon him back to the place where he really came from.
"The heck? What's wrong with this library?" This was his reaction when he entered the wide door and saw the numerous books surrounding him.
