Character Name: Vianca
Extent of what Zenitsu can pick up: All The Things
Notes for anything I should have Zenitsu pick up on: Vianca is the softest spoken, as you know. Speaks gently, doesn't tend to put a lot of emphasis on her words in the same way she does not emote usually. (Read: its monotone, bro.) She's getting a little better about that though. She is also working on becoming comfortable with raising her volume.
Anything else: Every once in a rare while, he might hear a little buzz from her back when her wings re-adjust under her shirt. Mysterious.

Character Name: Kaito
Extent of what Zenitsu can pick up: All The Things
Notes for anything I should have Zenitsu pick up on: He's a very Honest boy, usually, even if sometimes he will say things he simultaneously believes but also knows are full of shit. ("Oh yeah I made a ton of friends in prison" etc. etc.) Generally he doesn't have anything to hide and usually lies via omission if he has something he needs to keep on the down-low. His tone is usually pretty even and low, but Zenitsu will definitely know if he's pissed, even if he doesn't raise his voice that much. On the flipside, his tone does get a tiny bit softer with people he's fond of.
Anything else: The smiley face whispers.