I tweaked the translation a little -- I think she's asking, "Who is [Fujimiya-san]?" as rhetorical question implying that he needs to refer to her more respectfully. Like when a parent pretends not to understand a kid's request until they say "please".

Zatokechi said:

I tweaked the translation a little -- I think she's asking, "Who is [Fujimiya-san]?" as rhetorical question implying that he needs to refer to her more respectfully. Like when a parent pretends not to understand a kid's request until they say "please".

she is not actually. どちら様 "dochira-sama" is a politer way to ask "who are you?" then using 誰 "dare". it's used when you're addressing someone you don't know, like at the door or on the phone. it's like asking "may I ask who's calling" or other polite greetings.

her face would suggest a suspicious tone, so I put it as "...and you are?", but she is still speaking politely

she is not actually. どちら様 "dochira-sama" is a politer way to ask "who are you?" then using 誰 "dare". it's used when you're addressing someone you don't know, like at the door or on the phone. it's like asking "may I ask who's calling" or other polite greetings.

her face would suggest a suspicious tone, so I put it as "...and you are?", but she is still speaking politely

Ah. I don't quite understand why she would be saying that... what would that have to do with d/s?

Zatokechi said:

Ah. I don't quite understand why she would be saying that... what would that have to do with d/s?

It doesn't really. It's just a cold, suspicious reaction to someone she perceives as a stranger, like how she acts in the series to Hase at the beginning.

So, since he a masochist in this gag, he's enjoying her cold reaction