Evil Is Sexy: Actively averted, as whenever a beautiful-looking character is doing something villainous (especiallyrape) they will either have extremely distorted facial expressions while doing it, or they weren't pretty to begin with.
Downplayed with the unnamed conman with a bandana who was the Arc Villain in chapters 34-38. He has some menacing facial expressions, but none of them reach the point of Uncanny Valley, and therefore his looks aren't very hindered, even when he makes an Oh, Crap! face when things go south for him and his gang.
Fan-Preferred Couple: Jae Yeol/Jay and Hyung Suk/Daniel. The fact that early on most female characters that directed their attention toward Hyung Suk/Daniel only did so for his new body's looks and that Jay does NOT judge people by their appearances and is willing to get beaten up and even face his fear of dogs for Daniel's sake only made it all the more appealing.
Fridge Brilliance: Why did Jae Yeol lose in chapter 49? He let his anger get to him, for Systema to properly work has the practitioner to keep a clear mind and not let their emotions get to them.
Olly Wang's admiration of James Lee and rabid fixation over Eli Jang goes beyond platonic levels.
Jerkass Woobie: Logan Lee, Daniel's bully turned out to be one. While he was always the rough type, it was only after his girlfriend cheated on him with a handsome classmate that he finally snapped and since than had developed a massive degree of Inferiority Superiority Complex towards handsome guys, with his bullying of Daniel being just one of his outlets. It doesn't excuse his past actions, but it does make them (somewhat) more understandable.
The Scrappy: Pretty much any bully (except perhaps the one with the bandana and who was more of a cocky conman than anything else, unlike the farmorebrutalexamples) and any of the guys and/or girls who are more interested in someone's looks than anything else.
Respect your parents, they are willing to go through all kinds of endeavors just for your sake.
Only your persistent hard work and efforts can help you overcome people's (initial) perception of you.
No, even if you are discriminated by society because of your ugliness, just screaming around like a Spoiled Brat and never facing the challenges of life head-on by using said past discrimination as an excuse, is NOT an option.
Ron the Death Eater: Some of the female characters get this treatment, especially Daniel's possible love interests and ESPECIALLY Zoe Park/Park Ha Neul.