My wife just told me her next character concept and I can’t wait

We are big on role-play in our games but still like to get silly. She typically plays Caster classes but said she wanted a change. She came up with the idea for being a barbarian that’s a passive-aggressive people pleaser. She would always try to act smiley and hide her real feelings. Whenever she goes into a rage she would refuse to admit it to the party even as she goes full berserker on monsters.
I’m her DM and I feel like this will have a lot of potential for goofiness and also get real and explore how it feels to live like that.