In 013, Ultimecia is the one who tells Kuja that his memories are implanted and fake, which upsets him. After he leaves to start going after Zidane, she calls him a "foolish child." Later, Garland chides her for breaking Kuja's spirit, but Ultimecia shrugs it off by saying that her words have motivated him.



Maybe "hate" is too strong a word, but I don't think she likes him much.