I'm not sure, but up to this point, I suspect that Joshua's maid (Fiore) is Satella's sister? Maybe she thought the hornless demon was Chrono because he resembles Aion, who must've taken Fiore during the fire. I don't know; even the pursuers mixed those two up when they were smelling Aion, but figured it to be slightly different, which was Chrono's scent. Plus, the part where it says Joshua and Fi must be attached to each other because they're both "missing something" could be that they are both missing their sisters (Rosette and Satella).
Bam. We'll see if I'm right X] hehehe C: