I don't know; maybe I'm just slow. I just made the connection in my mind about the titles of the two Ari eps, "Bete Noire" and "Reveille".
Bete Noire = Nightmare. (Okay, so technically it's "black beast", something hated or despised, but let's go with the writers' definition here.)
Reveille = Awakening. (Again, not actual definition, but close enough.)
I didn't realize they were so clever. Huh.