The sly yet sad way Zhang Guo says she doesn't agree that she's always considerate... I have to wonder if this fake engagement isn't because of just how tired she is of being propositioned, but the lie makes her feel guilty.
idk about guilty... a ring can be a great conversation stopper, for those who need one on the regular, if that's plan she went with... fake or not, she probably wasn't expecting any of her (straight) coworkers to show her that face of disappointment, when they noticed the ring on her finger.
https://dynasty-scans.com/chapters/a_fruitless_betrothal_ch02#2
these closeup panels at the start felt like a cut from some shounen manga where the mc gets confronted and does two pages of mental gymnastics in the blink of an eye - that kind of recalculating pause from a super in control and calculating person.
like, it was outside her calculations in that moment, but a few chapters later and it's starting to look more like she found a new plaything...