It makes sense that helping Risu would help Nikaidou figure things out regarding Aikawa. Given that he has the eyemarks, it is difficult to know for sure, but this seems to be the boss when he is controlling his sanity. Though the cause of him being berserk is Risu’s curse. You still have to wonder why Aikawa killed Risu, but it makes sense that he would seek out Risu’s magic. It makes sense that Ebisu’s magic is what cursed Aikawa into Caiman since when she died, the curse wore off.
We see after using a use of time magic that Nikaidou is turning more into a devil with the tail. According to Asu, there shouldn’t be cause for concern, but it is hard not to be concerned. Though it seems the effects of turning into more of a devil have Nikaidou fulfilling her desires, which makes sense. For Risu we do see more memories of the Curse inside of Caiman, but it is difficult to make out what it means.
Things turn to shit with the CrossEyes, with Dokuga nearly getting killed, and he is about to be interrogated by Shin’s group. We see a member of the CrossEyes take out everyone so he can have Black Powder all for himself. It shows that even if the intention of the foundation of the group had good intentions, the greed can be shown, like here. He doesn’t even know the big thing is the boss. Fujita was able to take him out, but it would be sad if this was how he met his end.