Having just finished reading G-senjou no Maou, I am naturally awestruck and cannot help but present one particular character. It seems characters with the name Kyousuke have a flair for being amazing.
Azai Kyousuke (G-senjou no Maou)
I love how quickly G-senjou throws all ambiguity regarding this guy out the window. The best anti-hero I've seen in quite a while.
Why I like him
It's going to be hell trying to describe Kyousuke without spoiling like half of G-senjou's plot, but I'll try as good as I can. Kyousuke is the adopted son of yakuza boss Azai Gonzou, who is to be blamed for Kyousuke's current situation. He helps with his father's work, but not because he likes being a yakuza; because he wants to pay off his debt. The reason he became Gonzou's adopted son is because his father left with a huge debt, and Gonzou's loan sharks would show no mercy, and so Kyousuke starts working for him so that at the very least his mother can continue living. It goes without saying that Kyousuke cares little for his foster father and would probably kill him if he could.
But that's just one side of Kyousuke. On the public side of things, he's just a normal high school student, albeit the brother of a highly successful ice skating prodigy.
Enter Usami Haru. A rather strange girl who transferred to Kyousuke's school with the apparent goal of catching a person called 'Maou'. Shortly thereafter, Gonzou also tells Kyousuke to catch this person, because they cause trouble for the Azai Corporation. And this is where the plot really does throw out all ambiguity regarding the connection between Kyousuke and Maou, for you see Kyousuke is a "frightfully forgetful" person, suffering from "headaches which cause temporary memory loss on recent events". Seeing the plot unfold with a perspective switching between the Kyousuke who knows nothing and the Maou who is the mastermind behind all the events makes for a very engaging plot.
Kyousuke is a character with quite variable character development depending on which story route you go through which is always great. Sometimes he turns into the most sadistic monster imaginable, other times he becomes a most loveable Paulus-type character. There are several more reasons why I love him, but discussing those would be inevitable spoilers. I already spoiled too much, although it's mostly from the first 2-3 hours of gameplay.
I shall leave you with this image of our most beloved Maou.
2015, you better live up to the expectations I now have of you.