The Amulet of Samarkand

Nathaniel as the main young protagonist is stubborn and at times indecisive. But his stubbornness and indiscretion often pays off. He crosses paths with the (not so) powerful genie Bartimaeus - a demon with a narcissistic nature that doesn't irritate the reader with its hubris, but instead greatly amuses and makes us adore him even more.
So we have two characters with completely different characteristics, but who complement each other so beautifully and go hand in hand. Although they would sometimes prefer to strangle each other, there is a strong bond between them and we as readers witness some bromance moments.

The trilogy had me laughing so many times that I was clapping at some passages for a week. It's been a while since I've read the series, but I remember it with a smile, and maybe I'll read it again sometime to remind myself of Bartimaeus' colossal drama.