Plethora! Truly a hard thing to narrow.
For me its :
-Johan from Monster anime.
- Light from deathnote
-Kira from jojo
But cutting it close for me would be between :
Griffith from berserk
Just the symbolism of going after your dreams is taken to a whole new maxim with this fellow having him drive past insanity mark.
And this guy :
Makishima from psychopass
His curt yet embelished way of speaking has influenced how i produce all of my villian characters. From his philosophies to his charisma.
That and all these characters are attractive so