"No, I have more important things to do." Damian brushes you off while his hand is still sketching in his notebooks. It's not really important, but it's the only excuse he has to not tutor you. Well, first; Damian is no teacher, second; you are his twin. You share the same intelligence as him, so what's the point when you can easily understand the subject? Damian can even bet you're the smarter one between the two of you.