You're the one making it a big deal by overreacting. [Shun had meant the earlier comment to basically be in passing, a warning that Yata might not necessarily make the right choice without the person who the cat is actually for here. As far as he's concerned, it's Yata's fault it went any further than that.]

Anyway, some idiot's probably going to get nosy about it eventually, so you should learn to keep a better poker face. [In Shun's definition, most of the people who get nosy about that sort of thing are idiots.]