Zero doesn't actually hate Okita. Zero is picky about vampires and more lenient to those who do not like what they are and want to change it. Wanting to not be a vampire gains many points with the Zero. Which of course is the opposite to vampires that are fine with what they are, like Ion, which gains negative points with the Zero. Also, Okita seemed to actually being listening to what he had to say, which is another thing that makes Zero less prickly, cooperation. Aside from that, Zero was too keyed up because of the situation to develop any concrete opinions.

What would be the ideal pet for Ino?