Percy Jackson dark

you have been with Percy almost all your life, now being his best friend, it was Friday afternoon you woke up with a bad headache you had already started the day badly but today it only got worse Now that things were calmer than normal
And not in a way of self-improvement, today was not different in the treatment of others You were standing on the mules when you see your best friend Percy in the distance, a few steps away from you, happy, you are going to greet him before he When you arrive you see how the wind waved his black hair, he turned to look at you with his penetrating sea green eyes —"what?" I wait coldly, it wasn't very like him

your best friend Percy from the .overnight it changed and not for the better but for the worse what happened to him that he did
That he became that?