This episode gave a lot of fuel for the "Kaito is connected to Darkiine/will become a bad guy" theory.
>he now has a canon reason to disappear from the story as Kaito (going back to his idol activities)
>he shows interest in Cures fighting monsters, but he doesn't know who they are
>Uta caught the feels for him, which means he has to be put in some danger for that to pay off
>he acted noticeably colder/more serious towards Cure Idol compared to everyone else
>Meroron and Purirun are very obviously forced out of the scene when he meets Idol, they see him, but he shouldn't see them for whatever reason
>the scene of him showing up is immediately followed by Zakkuri once again begging Chokkirine for more help
I just can't imagine it going any other way.