She casts Imp and Drain often, and she can also use the dangerous Overture, which forces all physical attacks targeted at Coco to be absorbed by the target of Overture (similar to Cover). Coco also uses Slap, which silences the target. The quickest way to defeat her is to cast Rasp on her, as Coco dies when it's MP reaches 0. Since she only has 198 MP, a single Rasp should do the job.