So this is where Gareki's story and the Circus's story meets (and definitely Nai's as well. See that old man there, Erisyuka's grandfather?).
When we looked into Gareki's past a couple of episodes back, it was pretty clear where his story will meet the plot add to that Yotaka's transformation last episode and we get the complete idea on why will Gareki actually stick with Circus (or so I think). Gareki's vengeance against the person behind Tsubaki's death didn't ended the way he wanted. Sure Hirato killed him but his death didn't felt anything more than another person's death because he wasn’t the one who did the honors. The fact that someone else killed Tsubaki's murderer will never satisfy his hunger for revenge. SO I guess that's where Gareki's actual entrance to the Circus will happen. He'll probably help stop Kafka's stupid experiment of turning people to Varuga.
Now for Gareki's intention on switching to the dark side (fufufu >:]), it looks like he's got some good cause behind it. Of course what do you expect from some tsundere to do anyway? As I have mentioned last post, Gareki's the type who'd take care while hiding in the shadows. He doesn't particularly want to be praise or something. Behind all those you should never get involved with me talk to Yotaka, he's actually paying for Yotaka and Tsubame's grandfather's hospital bills. He just doesn't want them to know because he's that kind of person.
Aside from all the Garkei's moments we had in here, we get to know a few more stuff about Varuga and Kafka and Tsubame joining Circus. She wants to offer herself for experiment purposes so that Circus will have more information on Varuga. Well that sounds scary x_x
Anyway with Gareki's arc concluding, I'm hoping to see what's really going on with Karoku. We kind of left it hanging since Gareki's failed abduction. AND see how they brought out Karoku's notebook about Nai. I'm pretty sure we'll go back to what Karoku's actually doing with Nai.