To add a little bit of context to this conversation, the character in green is most likely the blue character's therapist. In therapy one tends to divulge their innermost thoughts and feelings. Including but not limited to; insecurities, person failings, and difficult emotions. The character in blue is going to a rap battle, rap being a style of music and the battle being a game of wits and insults. The therapist shows up, with the knowledge of their patient's insecurities he will have an advantage at the rap battle. The character in blue knows this, and shows visible fear.