I notice fierce, sassy female leads like Melissa here tend to be on par for Korean webtoon/novel series in general. The leads can be very blunt and unafraid to swear out things/people they dislike.
Compare with Japanese female leads who despite being firm and determined, tend to be very calm, gentle and ladylike. In fact, a survey carried out by a freelance otome game developer found out (among other things) the gentle yet determined personality is popular with their audience because "it's natural to want the heroine to have a good personality". https://uguucageoflove.files.wordpress.com/2020/05/2020-05-15-23_14_16-otoge.xls-openoffice-calc.jpg