Narrowed eyes and a suspicious stare that you won't likely miss; however Gin is no fool. This is a crowd of people, and you could both easily make a scene before he does something himself. ...IF he does something. Let's not jump to quick to getting his hands dirty now... He'd rather be certain of things first.

Still. There's a smirk on his face that's just as hard to miss if your attention is on him. Congratulations Conan- this is beyond mere amusement now.