episode 31 was peak, not much to say. I suppose Kyo is going to slowly let Nirinso be open to the public (or, at least, for the people that can't keep their partners). Maybe that's the end goal of the Nirinso shrine - at some point, more people (probably children) are going there and getting their own partners
As for the preview, I just noticed that we have high chances of the IceLeomon being Maki's (dead) partner
The tradition continues lol
So my theory is: next episode is Maki's backstory, her IceLeomon was her partner (I wonder if she used to be the Water Star) and in the present they are going on a mission that happens to involve their murderer. Bonus points for the IceLeomon being a fan of coffee, hence Maki making some of it in the preview