She's that weird person that holds grudges against others for no reason. She just saw that her Manectric and Crimson's Luxray would make great rivals, and then seeing his performance actually intimidated her and now she wants to be his rival and enemy. She just hates Miel because he found her out so easily, and she's just really transparent. Every time Miel shows the true colors of a bully, they immediately hate him and want him to suffer because they feel threatened by him from his all-knowing knowledge of how the human mind works. Remember, that associate's degree in his path to psychology isn't for nothing XD he wants to become a psychologist and a therapist.