User blog comment:Inept Wiki User/Speculation: The other Celestial Spirits/@comment-4829046-20130612024404/@comment-7418318-20130612150136

I'm not saying they do for sure, but we havn't seen confimation either way, so it's at least possible that silver keys have less restrictive contracts than the golden ones in this regard.

After all Caelum didn't join Lucy like Angel's Zodiacs, even though he betrayed Angel at the end of the battle.

And the whole thing with the dissolving or breaking keys in the KotSS arc never made any sense to me, since the keys are items the celestial spirit mages use, but that aren't part of their magic. Also Angel outright said that she killed other celestial spirit mages and took their keys, both in the anime and manga, so why would the keys of Angel's victims stay intact and the keys of the Nevill desciples dissolve?

And even if Angel lost her old contracts, that doesn't stop her form forming new ones, if she can get her hands on her old keys, or find new ones.

As for Everloo, I don't expect to ever see him again (I certainly hope we won't), but we were talking about the existance of celestial spirit mages, not their possible presence in future mangas.