Hugo's face was red from holding back his emotions. He knew that Scorpius wasn't his Scorpius. He knew Scorpius was terrified of him and hated the idea of Hugo. That was why he'd left Scorpius alone. That was why he's stopped trying. Having it pointed out to him again was painful.
"Yeah. I know. But I left you alone like you asked, didn't I? I won't be trying to turn you queer. Don't worry."