Spoilers for season 2 episode 7 above. Reigen is simply the best character in Mob Psycho 100. He starts of looking like a generic fraud stringing Mob alone, and you might even dislike him for that at the beginning. However watching the show, you will come to realise that the relationship between Reigen and Mob is the most important relationship in the entire series.
They both need each other, and they both grow because of each other. The last episode is really special because you see how far they both have come from the beginning of the series.
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