That's really all he cares about: making a difference. What Matt does is always dangerous, but he's glad that Katniss feels safe, as long as she's not letting her guard drop. He won't knowingly ever put her into something that he doesn't think she can handle, that they can handle. That being said, he knows a day will come when they walk into something more dangerous than he expected.

That's exactly why they're tying him up and gagging him.

He can't help but smirk at her teasing. "Since I'm planning on hitting him anyway, go ahead and try both," he jokes, though he's not entirely sure how he'd feel about Katniss honestly flirting with someone or someone flirting with her in return. He's got the feeling he'd want to hit the man then as well. He knows how nervous she is, can hear her heart beating too fast and it's actually a good sign. She should be a little nervous.