Review based on reading Arc 5 and Arc 6 of the web novels (which is suggested after watching season 1 and 2 of the anime.)
Re: Zero is quite possibly my favorite anime right now. For a simple premise, of Returning by Death, it really has deep character growth and a massive world to explore. You essentially read about a boy, who doesn't believe in his own self worth, gain self confidence over time. There are huge obstacles to over come, and really creative solutions to huge problems. You will fall in love with certain characters, and you will begin to understand this world, and sort of wish you could live in it too. I'm really excited to see where the author takes this series.