The mysterious Rothwell boy is actually a younger Lenine.
Both of them have green hair (though Rothwell has a darker shade), wear smart, red and black clothes, and have the same slightly snarky/mischievous attitude. If this theory is true, it will mean that Mika's story is set at least 13 years before Micaiah's (given that Rothwell's age is apparently 7, and Lenine is 19 years old). The name Lenine Rothwell also has a nice ring to it... which leads to the next theory, that:Mika and Princess Micaiah are the same person.
This seems to be almost a given. If they aren't the same person, at least they are very much related. In Japanese, Mika Himeya can be rearranged to become "Mikaya-hime" (Princess Micaiah), which is a huge clue in itself. They both also have the same powers, cannot manipulate metal very well, and suffer from divine punishment if they hurt people. It is unknown how Mika's black hair and black eyes could have morphed into Micaiah's blue eyes and purple hair, but given that Chapter 3 reveals that Mika's magic can restructure people's physical attributes on a molecular level to heal them, it can't be too far fetched that she can somehow give herself magical plastic surgery... which probably explains why Micaiah is so beautiful. The fact the two girls were voiced by the same voice actress further support this theory as well.- Another piece of evidence is that the front part of their hairstyles are very similar.
Euphony is Mika's mother.
Lots of people theorize that Mika's story occurs before Micaiah's, but has anyone wondered if it actually occurs after Micaiah? Mika's mother also has red hair, like Euphy.Rothwell and Anyu are the same person... who is the Messiah.
The Messiah is described as a man with green hair and golden eyes. Rothwell is male and has green hair. His character design also makes it impossible to tell what his eye color is. Coincidence? I think not. Anyu is almost entirely disguised by the cloak, but his smile that we're shown is somewhat similar to Rothwell's. It would also explain why Anyu is as familiar with the castle layout as he seems to be in Chapters 1 and 2 - he's been there before.Given that the Princess seems to be on good terms with Alchemist de Lancaster, that the Alchemist tortured Mika and her boss, the Cardinal, murdered Rothwell's father, Rothwell would also have a reason to exact revenge on the Princess (which he does in Chapter 2).
Anyu possesses the same powers as Mika and Micaiah, except he can hurt people. That would mean that he is acting as Mika's proxy and exacting revenge on her (and his) behalf. Since Mika spent the entire Chapter 3 trying to find a way around the Divine Punishment together with Rothwell, she probably found a way to impart her own abilities to him (maybe, by restructuring his brain?) with none of the downsides.
