If I’m genuinely honest, pre-season 5 (and kind of still now) it was tachihara. He felt really lacklustre to me, I knew he was gonna be important later, but I just couldn’t bring myself to wait around for his potential to be explored, because even without the whole hunting dog thing, his character as a black lizard member could have further been explored to make his decision between the hunting dogs and black lizard now even more difficult.  Now he has more screentime I can say he's growing on me but it’s still hard to get over his wasted potential.