Demo's master is in fact, raocow himselfLook at the way he talks, and the fact it was raocow who came up with the whole vegetable thing.
Demo is from Gensokyo.Before fighting Rumia, she claims that there's something familiar behind the boss door.
Demo is much more sinister than she seems.It is a fact that everybody on talkhaus is Raocow (Except for the moderators). It is also a fact that Raocow is Demo's fursona. Ergo, everybody on talkhaus who contributed to the games is Demo's sockpuppet. Now just what had our cycloptic minion in mind when making the games? Is she trying to shape the world according to her will? Is she trying to get a monopoly of the world's magic vegetables? What if the various avatars in the developers' rooms are real people whom she has kidnapped, trapped inside the games, and then replaced? Why is Iris much less useful than she is? Clearly she's planning to somehow destroy the entire Universe for some unfathomable reason (And the Universe itself has tried to kill her just to prevent that from happening). That being said, I completely support her in her endeavor and hope there will be a suitably epic boss fight at the end of her quest.
Iris eventually becomes Psycho IrisThey're both purple, they both have one eye, and they're both named Iris. What more do you want?
Calleoca will perform a Kill and Replace on one of the main characters.Her "joining you and pretend nothing ever changed" comment was actually Foreshadowing for an infiltration plot. My money's on Sheath, due to how ridiculously easy that would be to pull off.
Serac is a Manipulative Bastard.It's just impossible to figure out to what end this is yet.
Calleoca is everyone.In the beginning of world 8, Calleoca claims that she has watched Demo from numerous different worlds and times, as she is a shapeshifter with extreme devotion to her facades. I propose that eventually, Calleoca would enact the lives of every single thing in A Universe Thing, up to and including the people who would bring about her creation. Mishi didn't actually wipe herself out of existence, she just knew to play along with the idea that she did, and since she plays everyone with devotion, it creates the exact same affect. In the very end, Calleoca will become Demo and play through the world she has constructed for herself.
Sheath has a loose grip on realityLiterally, which is why she didn't get erased.