User blog comment:FairyRaven/Fairy Tail Chapter 406: The Girl Within the Crystal, Review and Commentary/@comment-3075024-20141027185641/@comment-5840892-20141027200427

That could work as an explanation. Mavis is a relatively popular character in that section of the fanbase, of course I can see why, but I don't ever consider her to be a fanservice worthy character, just a bad-ass cute one.