Sakuya is jealous about the hair...too?

I think it's more of the "wife" stuff. Tima is a Sakuya/Meiling fan, and Sakuya is very dominant most of the time.
It could be just Sakuya not wanting Meiling to show herself to the people in the intarneths

I'm inclined to think the former. Bottom right and center show her comparing her own look and wanting to cut meiling's hair respectively.

Actually, bottom-right Sakuya is the "forehead-exposing" version of herself in her own "Wonderful Hairstyles of my Wife" (also by Tima).

As a perspective reference to his own work, maybe Tima's suggesting SDM could probably have a shared ("SDM Staff" or otherwise) bathroom, where Sakuya and Chugoku brush and clean up before/after bed.

As for the center, Sakuya's more resigned look (contrasted with her rather annoyed/disgusted look in any other panel; Sakuya disliking Meiling being "superfluous" with her hair?), to me, suggests simply that "it's time for another haircut; you've been letting it get too long, stupid China, stop playing around, etc."

MNT said:
Actually, bottom-right Sakuya is the "forehead-exposing" version of herself in her own "Wonderful Hairstyles of my Wife" (also by Tima).... etc.

Aside from the different interpretation on how she feels you're describing the same thing with added speculation...

Ponytail & sidetail <3