Alucard

he walked along the forest, keeping a grin on his face without any hesitation, pulls out a pistol and shoots at the evil spirits.

Whether or not the enemy is a mortal being does not particularly matter to Alucard, if they are to be offensive and hinder him from completing orders that he was given, then they are to be killed.
However, even with his incredible powers, it is possible to take Alucard by surprise, usually because of his arrogance. In his first meeting with Alexander Anderson, he assumes he had easily killed Anderson with a single bullet but is caught off guard when Anderson regenerates his wounds.
Alucard also expresses deep disappointment that Luke wasn't a worthy adversary.
Despite his disgust for homicidal vampires, he is not entirely against becoming something above human. Rather, he believes it is something one must earn. Presumably, he views his own transformation as an escape from death and a cowardly action of revenge for his wrongdoers. He happily let Seras choose to become something unhuman (despite his self-reflection) due to her indomitable will and courage, for continuing to fight against the monsters in Cheddar and not giving up even when she was about to die. Alucard states that resignation is what kills people, and once they've rejected resignation like Seras, humans gain the privilege of making humanity their footpath.
Underneath his arrogance, Alucard is deeply sad and appears to be envious of humans.
Alucard also has great respect for humans who have the willpower to endure old age and death because he had none of these qualities when he faced death.
All of these feelings are shown at various points throughout the series, such as when Alucard tells the Queen that she is the same "saucy filly" from 50 years ago and that now she is truly beautiful.
He becomes infuriated when Anderson stabs himself in the heart with Helena's Nail and becomes a monster, as he views it as Anderson making the same mistake Alucard made.