"Ah, Meridith," Yuki turns to acknowledge the newly arrived maid. "We were just discussing how best to introduce ourselves to the Prince," she factually states. "We were also discussing whether Lune's new uniform is 'darling' or... something else..." she leers with a wink.
Hopefully her reaction will be more amusing than the butler's, or rather, his lack of one.
The assassin then looks back over to Terran and arches her eyebrow. "How exactly will the Prince be taking his lunch? Will he be dining privately, or will we also be serving the rest of the estate's residents?" She is, of course, referring to the 'arcane adviser.'
Despite being a highly-skilled killer, Yuki sure can be oblivious sometimes...