Prob cause she's like too traumatized at this point and rn was acting nice so the ml doesn't get rid of her. I don't remember what happens around ch 44 but yea she actually does go through a bit of traumatising stuff but she then finally gets the support she needed and i think she becomes a bit stable, i don't really remember her being annoying tho, i always saw her emotions being valid.
Then again, i did like Ruby from the first so it might just be me being biased, i think she's written well for what she has to go through.
Maybe give it some more chapters

just started this and currently reached chap 44, please tell me this gets better lmao. i’m seriously confused and a bit irritated fl just switches through like 5 diff emotions and is constantly blushing when it comes to the ml it feels like this has been the same cycle every chapter i read.