For me it reduces a person's hotness if her personality is beyond bad. It eats away from the first impression, which is usually visual, when the character appears on the screen. Houki's favourite pastime is to be violent, disagreeable, dishonest (in an emotional manner), yet still obsessive despite those aforementioned qualities that only serve to push people away from her. So, what does it matter if she has a cute face and a sexy body? They are only wasted on her. Even somebody like Laura who knows more or less as much as Terminator about human relationships is far more loving than Houki.