It's as Ryoma's got his mouth over his crotch that he lifts his head and says, "Oh, you'll never guess what I heard today."
Izou wants to rip his head clean off, but settles for just saying he will instead.
"That's not very nice." He flicks Izou's clit like it's supposed to be consoling.
"Well, I, ah, I don't really fucking give a shit--"
Ryoma leans back and begins to button himself up at that, and for a moment, because he's, y'know, not really in the right human mindset, Izou kicks out at him like an animal. His wrists are tied behind his back because he refuses to do anything else otherwise, and he's caught in an unfortunate sort of "I want you gone, bastard," and "don't you dare leave me," that comes out in an all too needy whine instead.
"Hey-- woah, it's okay," Ryoma quickly says, because he's joking-- of course he is. Ryoma realizes that Izou is disgustingly fragile in some places and all worn and calloused in others but he can't tell all the time where the line starts and ends, and apparently it ends at pretending to not want to finish Izou off. He's unbuttoning himself, "It's fine. Hey."
Angry tears blossom up in Izou's eyes because he's ashamed more than anything else. Ryoma unties him.