
What happend to Hayoung ... I realy dont understand.. She start piss me of..

She was abandoned out of nowhere by her first and only previous girlfriend after a promise that they would stay together and support each other. It traumatized her and left her unable to find any trust in relationships.
Reread Chapters 36-38, and you'll be able to see exactly where all her issues come from.

https://www.google.pl/amp/s/aminoapps.com/c/yuri-manga-and-anime/amp/item/miss-angel-and-miss-devil/3WmB_dmDUDIgazKzPG541gQ15GPolE2oje8
Someone can translate this chapters?
Hahah! At last they kiss xD