What scene I mustve missed it.
It’s been a while since I last read it in Japanese, so I don’t remember exactly which volume it was, maybe volume 3?
But there is one (or possibly several) scenes where Yoruich, and I think some other characters as well ,wre talking in Urahara Shoten about Urahara’s true motivations: why he created the Hōgyoku, to what extent he manipulated Rukia, Ichigo and the others into this whole situation, and how he ultimately came out on top in the end even after that whole shit with Ywach.
It’s all kind of vague, and it was always implied that Kisuke is more of an asshole than his outward persona suggests. But hearing this from Yoruichi who probably knows him best (aside from, arguably, Aizen, since the two are quite similar) casts him in an even more suspicious light.