Alright, here's my theory on Dento. As you can see in the photo revealed today, there seems to be a Water-type counterpart of Yanappu, which has been revealed to be one of Dento's Pokémon.
In the August 31st news story on the main site, if you watch the 3rd video around 3:27, then you'll see that Dento has some puzzles set up around his gym, eventually teaching the player what type conquers what. Around 3:40, you'll see the badge that Dento gives you; it has 3 colored jewels or something like that in it. Guess what colors they are? Blue, red, and green. Baoppu is Water-type (Blue), Hiyappu is Fire-type(Red), and Yanappu is Grass-type (Green). My theory is that Dento will have each member of this monkey trio and will engage you in a Triple Battle for your first badge.