She was a girl who attended the Huntsclan Academy and took an interest in "Huntsboy 89", who was really Arthur Spudinski in disguise.
However another apprentice, Huntsgirl 23, also liked "89" and the two fought over him. They both were dates of Spud for a dance at the Academy which eventually led to a fight breaking out again between them after Huntsgirl 18 heard a rumor about 23 name-calling her.
It is unknown if Huntsgirl 18 was destroyed with the rest of the Huntsclan. She might have escaped the fate if she had washed-out of the Academy or quit.