Because you like Stu Price in The Hangover
Brilliant, violent, and only a little insane, the Joker doesn't listen to anyone except the voices in his head. See them in DC Extended Universe.
Howl puts the "tortured" in tortured artist. He just wants to be recognized for his work, but no one wants to trust a boy that sorta looks like a bird. See them in Howl's Moving Castle.
Dipper Pines is investigating a truly strange town during the world's wildest summer vacation. See them in Gravity Falls.
Ezio Auditore Da Firenze is a little short-tempered, a lot fun-loving. See them in Assassin's Creed Series.
Hiro is a free-spirit and remarkable genius who loves bot fighting and problem-solving. See them in Big Hero 6.
Jane Foster is an astrophysicist who suspects the colors in the sky may be a portal to another world. See them in Marvel Cinematic Universe.
After Otto Octavius' accident, he becomes fixated on finishing the reactor at any cost. See them in Marvel Cinematic Universe.
A good guy who's made some bad choices, Scott Lang is driven in his quest for redemption. See them in Marvel Cinematic Universe.
V is a violent anarchist with literally nothing left to lose. But, he might have a point. See them in V for Vendetta.
For Dana Scully, sometimes looking for extreme possibilities makes you blind to the probable explanation right in front of you. See them in The X-Files.
Fox Mulder is a devoted believer in aliens, monsters, and that the truth is out there. See them in The X-Files.
Twisted and seemingly soulless, Bellatrix Lestrange finds joy in making others suffer. See them in Harry Potter Series.