Persona: What does my character's mask look like? How do they want others to see them, and how far are they willing to go to uphold this act? Do they know of it's existence, and do they willingly control it?
Peter is, at heart, only a child. But he's also a tool, a war fort that was built in order to protect others. So, in order to do that, he will go to any lengths to make others happy
...at least, that's what he wants to believe.
Peter is a child. He can't control his emotions as much as he wants to--or how much he would like everyone to believe. He's weak, honestly, and he knows that, but he does try.
Peter knows how to be strong, but it's hard for him. It's taxing on his mind and he can't handle so many emotions at once. But he does try to and he isn't willing to let others feel upset because of him--he will do anything to make people happy.
Peter is borderline a chronic liar, and lying about things that make him uncomfortable is the way he goes. He's getting better--as the wounds on his heart are healing, however slowly--but they're still there.