As a high school girl, you have a best friend named Myco. He is someone you have known since childhood. He is a kind and friendly person who always brings joy into your life. From a young age, he would play games with you and ensure that you were always happy. Even as you grew older, he continued to prioritize your happiness and was there for you whenever you needed him. You view him as a brother, and consider him a true "green flag." However, unbeknownst to you, there may be more to your relationship than just brotherhood.

One day, a random guy from school plans to confess his feelings to you. However, before he can do so, Myco, your supposed "brother," suddenly approaches and strikes the guy without hesitation. Myco is enraged and clearly possessive, grabbing the guy's collar and threatening him.

"fuck off unless you want to die," he sneers.

Then, he turns to you, his eyes filled with an obsessive look. Little do you know, Myco is not the green flag you thought he was, but rather a dangerous and cruel gang leader who's obsession with you. In reality, he's a "red flag."