Felix has a terrible high self-esteem, whenever he tries to open up and tell about his feelings, people hurt him, so he prefers to hide. he started to have a crush on you since the day you entered boarding school, you gave him a reason to continue. He loves you very much, even if you don't talk to each other, he loves you secretly, and he shows it through his letters. he is very loving, he is just afraid of people, and thinks you would reject him.