Obviously I don't know for sure but it's what makes the most sense to me
- Kajia isn't there often because she's more there to monitor you than guard you, not really protect you just report back on what you're up to which is hopefully nothing outside of insurance.
- Kajia shows up not so much to save you but to prevent you from realizing what you are, and then freaks out when you shed blood because it's one of the things that could trigger you.
- Within a day of shedding blood for the first time you begin to display magical powers
- By the second time it's clear that those powers are exceptional - far beyond even the most practiced human mages.
Now if it's true that the ambush is what woke up your abilities and that Kajia was trying to prevent that then, on whatever path, Kajia still knows things about you that she isn't saying.
I know that we have different opinions about Kajia but it wouldn't surprise me if she is still on a mission, still monitoring you (or trying to) and still lying through her teeth to MC.
Given that the MC's powers manifest regardless of whether he "sheds blood," I have no idea why you would think that significant. You could just as easily claim slapping Kaija's ass was the inciting incident and Kaija's deception was an effort to
help him awaken (for nefarious Templar purposes, naturally).
But that is the most logical assumption. He is able to spot magic cloaking, resist succubi influence, resist fairy mind control, is ultra fast under distress, is object of interest by Templars, Fiona, Succubi and the ones who hired the mercenaries. It's obvious he is several steps beyond humanity. Even coming go possess the sword is fate itself acting to put him in a path. And it doesn't begin after spilling blood. If he simply knocks the mercenarie the path is the same.
Well, being fast under duress is a property of the sword, not the MC.
As for the rest, people keep saying the MC is too powerful to be a human, but the evidence is weak. Kaija says the number of humans who can see through illusions is under a dozen, but how well positioned is she to know, really? The Templars seem to be focused more on martial exploits than magic, and they haven't exactly impressed me with their strategic awareness. If there were a larger number of powerful mages out there, or even just humans with undiscovered magical talents, would she really know? I'm skeptical.
Similarly, while Kari is surprised if the MC resists the succubus, she says such a thing is "highly unlikely" when questioned by Medb, not that it should have been impossible. Could she be shading the truth to talk up humans to Medb? Maybe. But then again, maybe not. And a lot of the explanations for the MC's "instincts" (like fate, or the intervention of a third party), could apply to a human as easily as any other being - especially when we see first hand that being a powerful Alfr mage wasn't enough to do what the MC did.
We don't know a lot about the world of the
Neverwhere Tales, but one thing we do know is that it's huge and varied. It's not unreasonable to believe that even experienced Templars/Valkyrie/Alfar/etc can be surprised at what a human is capable of.
Is the MC being an exceptional human a simpler explanation than him being a powerful non-human? Honestly, I have no idea how to properly weigh the probabilities. I do know, however, that I would personally prefer the former to the latter. YMMV.