Chosen him one too many times, actually. Allen's quite tired of being told what he is, or isn't, or is supposed to be; but that's a story for another day. The fangs, threatening as they may look, aren't what he's wary of. He's used to seeing those, albeit bared in smiles that were far more sincere, and this is exactly where the resemblance between Alucard and Crowley ends with a whole lot of finality. Regardless of whatever Alucard's body language may be telling him, Allen knows beyond a doubt this man, or whatever he chooses to call himself, is dangerous. For him, the evidence is smoking high enough to obscure the sun itself, even though no one else can see it ― just this shifting, pitch-black aura around Alucard's person, massive and absolute. Makes it difficult for him to focus on other aspects of the vampire's appearance, but he does, eyes going straight to the glowing pentagrams stitched on the man's gloves and boring into them. His hasty dash here has left his white bangs in disarray, and should Alucard take a closer look, he may notice a matching, pentagram-shaped scar on the boy's left brow.

At the sound of the gunshot, Allen raises his left arm a fraction, not enough to be threatening, but he's definitely on guard. Sunlight glints off the strangely metallic-looking claw in place of his left hand, making the white cross etched on its back gleam; and somewhere in the back of Allen's mind, a voice is telling him his master might have found this situation really bloody funny.

He's not entirely sure who thought that.

"I've never been a fan," Comes the clipped reply, and the way his voice's wound wire-tight says Alucard is slowly but systematically getting to his buttons. "Of God or demonstrations."