Wow this was refreshing. I have encountered other Japanese BL mangas where the Uke is the buffer one but it’s bot as common. Usually, In Japanese BL, even if both the Uke and Seme are similar build, the one with a cuter/prettier face or is also slightly shorter is made to be the Uke. In this one I really was not expecting the Buffer one to be the Uke-how refreshing. And the Seme is actually skinny and frail not “illusion skinny” (where he’s actually pretty built under the layers)
Love You, Satsuki!