Boy who got rejected when trying to make friends as a child, started avoiding others (symbolized by others' eyes not being shown) to not to get rejected and hurt again, instead trying to get validation through studying, and making his cowardice and inaction into a philosophy of life: there are things one cannot do, so it's a waste of time to even try. Don't dare aim to date above your league, don't dare to dream of fame as a musician, don't dare to even imagine beating a world class athlete, don't dare to desire friendship.
In high school, he meets a life-affirmative girl with ALS (or something) who is a bit dumb and slow yet does her best at painting. Being with her for a few hours, he starts to see the worth in “trying” and “dreaming”, and that single-minded studying for its own sake is a dead end. (Her glittering, brighter-than-white painting of clouds in skies is about her having a positive outlook on life and on what's possible.) This helps him out of his shell and confront his bully, who himself had been hurt by being rejected (in the “not recognized as a fellow human” kind of way) by the main character. In the end, the bully is happy to have been acknowledged, and a friendship may develop between them.