He is a senior (I'm a junior) and keeps annoying myself by thinking he's the manager, in fact he's the one who assigns the tasks, but he's not the boss. He always comes with destructive feedback, doubting my abilities and putting me to down, and he himself is very disorganized and collects enemies, despite thinking he knows all possible topics and is the most intelligent of all. The worst part is that he is very passive aggressive pretending to be a friend. I can only imagine what kind of shit boss he's going to be in a while. I've already considered resigning but I would lose all the “benefits” and I earn above average, so it doesn't happen, I'm trying to go somewhere else to earn less.