Because you like Sebastien Michaelis in Black Butler

An infamous vampire, Alucard is a one-man killing machine with a philosophical side. See them in Hellsing.

If it means fulfilling her ambitions, Satsuki Kiryuin will show neither shame nor hesitation. See them in Kill la Kill.

Fiercely independent and extremely hot-blooded, Ryuko Matoi prefers to work alone. See them in Kill la Kill.

He's the great Black Star, and he's come to assassinate you. See them in Soul Eater.

A gentle alchemist who is soul-bound to a giant suit of armor, Alphonse Elric is growing into the responsibility handed to him. See them in Fullmetal Alchemist.

Years of brutal winters, foreign invasions, and crippling loneliness have left Russia's mental state far from wholly intact. See them in Axis Powers Hetalia.

Sasuke's quest for vengeance is above all else. See them in Naruto.

For the sake of science, Kurisu Makise will persevere no matter how deep into the dark secrets of the world she finds herself. See them in Steins;Gate.

Kagami Hiiragi keeps her grades up, helps at Takanomiya Shrine, serves as class president, and hangs out with her friends. See them in Lucky Star.

The witty Aku would be an ideal dinner guest, if he weren't a demon. See them in Samurai Jack.

Firo Prochainezo is swept up in a world of mysterious women, alchemists, and rumors of a wine that makes it drinkers immortal. See them in Baccano!.

Years of being the less desirable Vargas sibling have given Romano quite an inferiority complex, as well as the temper to match. See them in Axis Powers Hetalia.