Some may disagree, but I believe that this manhwa deserves more recognition than it gets. It's a manhwa revolving around a teenage boy, Joonwoo. Joonwoo is alone, has no friends and constantly gets bullied by someone who he considered his friend in the past. To make up for his loneliness, he find his resolve in an application called Random Chat, the app is as the name describes, 'a random chat' with a stranger.
Joonwoo matches with a young girl the same age as himself on the application, to his surprise, it turns out the be his classmate. Due to his awkward and shy nature, he cannot bring himself to tell her. Joonwoo talks to this girl through Random Chat, slowly building a strong bond with her whilst still keeping his anonymity. The girl tells Joonwoo everything about her feelings, how she wants to get with the class president, Joonwoo helps her behind the scenes despite falling for her himself.
This is story based on the hardships some may have faced during their schoolyears, bullying, love, toxic relationships, etc.. I suggest you give this a try at the very least. I think it does a good job at showing emotions and mental state through their characters.