In the world they lived in things were never as simple as the way this girl was framing it. Yes. He wore the costume. Yes. It was because he didn't completely trust his team mates yet (Well, not enough to take off the mask at any rate). In his defense though, once a person has seen people they loved murdered right in front of their eyes, well, they become willing to go through a lot of funny rituals to prevent again.
"I've got a lot enemies and I've only just joined the team, alright? I know it's weird. But if they really want me here at this PR party making an appearance, well I think they can make allowances." He finished a bit stiffly. Why did she have to go and swear so casually like that? I wasn't impressing anyone. "Besides not everyone who walks through those doors is a super hero. Who are you? I don't remember seeing you on any roster list. You could be reporting to Baron Zemo for all I know." The Avengers tower was still mostly a public building with people walking in and out all day. Most of the Avengers had public identities. Peter did not. It was pretty straightforward. "Look. I'm not even planning on staying here for very long. I've got my own family to get back too. So can we please start over? And stop looking at me like that. It makes your eyebrows look the like Sub-Mariner." Peter finished then and stopped to lift his mask up to his nose. He took another sip from his glass of punch and waited. Let's see if she is going to continue to react like grouch.