[It isn't just this moment, of course. He's noticed that Keith leaves the room sometimes when Shiro's exercising in the morning, incorrectly assuming it was because it made him uncomfortable to see all the scars-- and there are a lot of them, some more faded than others.]
I didn't think it was the scars that bothered you, just... [what they represent. He knows you're not a colossal dick who'd judge someone for it, even if he is, admittedly, self-conscious of them.]
[He looks relieved by the response, in any case. And his eyes dart down to look at his scars in turn, his gaze lingering despite himself, tracing over the large one on his shoulder.] [...]