@Yuya Kenzaki these are good ships! I'm not up for poly ships that much, but, I will say Training Trio!
Ok, so as it was just Kaimaki, Kaito notices that Shuichi was lonley, since Kaede died. So, Kaito decided to talk this out with Maki. They decided because they trained a lot they should let him in their relationship. And that's what they did.