A  

In essence, Mr. A is a parasite who views Shinichi as a threat. Reiko refers to him as a fool, while Migi describes him as "not one of our smart ones." Unlike other parasites, Mr. A lacks the ability for subtlety or deception and openly uses his shape-shifting powers in public, believing that he can escape harm by fighting, fleeing, and altering his appearance. It's worth noting that Mr. A is actually Reiko's father, and Shinichi must battle him at school when he tries to track down and kill him. Despite injuring him severely, Shinichi and Migi are forced to escape before they can completely destroy him.