[[WMG: Hiro is becoming a Royal]]
As his servitiude to Hime continues, he's able to access his "other side" with more self-control and for longer periods. Basically this involves increased strength and agility with [[Main/RedEyesTakeWarning Red Eyes]] with Main/HellishPupils. Exactly the same traits Hime herself has. We've seen other Blood Immortals; but they haven't shown the same multiplication of strength that Hiro has.
* It's possible that becoming a Blood Immortal Servant turns one into a classic monster, and Hiro was a Main/MillionToOneChance of a mutation into the Royal Monster category.
* Or maybe he was a Royal all along; who was punished by becoming a human for some reason. The Blood Immortal bond is just breaking through that conditioning. His sister may have been a former (non-blood immortal) servant; or more sinisterly, someone left to keep an eye on things and is reporting to someone else.
*** Sherwood has commented on how Hime "hasn't told Hiro everything" and that he'll "become a very strong Blood Immortal."
[[WMG: The Paperbag man of Akasabi Village survived being killed by Hime.]]
Severely weakened, he had to take lesser souls to survive, but he was permanently destroyed by [[Manga/SoulEater Maka.]] She refers to him as Sonson J, the killer of Emerald Lake."
[[WMG: Francette is going to get a CrowningMomentOfAwesome by mirroring the [[Anime/TengenToppaGurrenLagann Giga Drill Breaker]].]]
[[WMG: [[WesternAnimation/SouthPark Kenny]] is a Royal's servant]]
[[WMG: Sawawa has experience serving monsters]]
That's the ''real'' reason of her WeirdnessCensor...she is just used to a lot of those things. In fact, she perfectly aware 90% the people in the mansion aren't humans, it's just that nobody asked her if she knows that...she is probably unaware of the "Royal Family" and the whole battle thing, though.