User blog comment:SpookyBoogie27/Light Novel Spoilers/@comment-94.129.209.103-20130207073745/@comment-33447191-20130207075206

My first impressions of her weren't too good, mostly because she had the attitude of a High-Class Devil and acted in a way that irritated me. Needless to say, she wasn't one of my favorite heroines, up until Volume 14, where I started looking at her in a different light. It's shown that she's extremely loyal to Issei, helping him out in so many ways as his manager and all. Anyways, she's up there in the top rankings for me, also Volume 14 explains in depth  the reason that Ravel fell for Issei in the first place, she even tell him how much she started to think about him after the fight between Issei and Riser back in Volume 2.