Hopefully he absolutely kills it as a maid and Wakao's the one who gets all flustered instead.
I think ideally - if this is going the route of romance for them - is that Mizuno actually gets attention from girls dressed as a maid, and that spurs Wakao to jealousy and worry. So far she's the only one that can be argued to have actually caught feelings, between the two of them, but otherwise a good chunk of the "why do I feel uneasy right now" is coming from Mizuno.
Mostly to have more evidence that there is something bewteen them from her end.
Anyway thanks for the TL