While the first time I stated this, the case was literal, in this scenario, it is a bit more metaphorical.
The pieces have lined up perfectly, and now my plan finally comes to fruition. In a journey like this, it is this pivotal moment, the point in history where one can simply look back and smile at the perfect way things fell into order. Like pieces on a chess board, the king had been cornered, the defenses cast aside, and the queen brought into full view. But enough of my metaphorical banter. I am too satisfied right now to care about secrecy.
A little while ago, I met with a certain someone... Sora... It is true what you said Heartless, you are the true physical manifestation of darkness. However, since Sora is not a manifestation of the light... Not a Princess of Heart, or PoH as I have taken to calling them, his heart spawns darkness anew in the absence of the darkness that has cultivated into existence. So? This is the darkness I have taken. Oh, do not worry as you often do. Sora is perfectly fine. I have not harmed him as you asked me, and not a single hair on his spiked little crown have I harmed. All he had to do was stand there... Open up his heart to the festering blackness within for a single moment... .Oh, how it was marvelous. The twisting black tendrils, the roaring scream of power, and the rippling shockwave of darkness upon light... It was almost poetic the way the darkness so easy took over his body once he was open to it. I cannot deny that I was sorely tempted to let him succumb to the darkness within... He would truly be a wonderful asset to the cause of Darkness and of the pursuit of Knowledge...However, in all the blackness of my heart, I do keep my word. With a single swipe, I summoned forth the Dark Keyblade... The Heart Unlocker from its small pocket realm where it had been stored. The Dark Keyblade was as sinister as before... still incomplete, it served the same purpose as it did amongst my Heartless. However, I have made a few short modifications to its nature... I would now use it to extract the darkness from the consumed Sora...
And it went smoothly of course, as most of my plans do. I successfully extracted a large enough portion of Sora's inner Darkness, so that he reverted back to normal form. Quickly, I transferred it into a containment device, which I now hold in the palm of my hand... Sora, I do not understand why such a powerful warrior as yourself cannot comprehend the power within... A swirling vortex of crackling energy... a blackness so twisted and vile, that the brightest of lights cannot hope to extinguish its chaos... A hurricane held in a bottle...
I left you soon after that, although I doubt you were able to see me go, as you were still recovering from our 'operation.' Rest assured that our deal remains affirmed. I hate to bring your friends to the truth, but unfortunately there is no other choice at the moment... It appears I underestimated the connection between you and your Heartless/Manifestation of Darkness... He knew of my plan the moment you did... It matters not though. I did not reveal to you how I would be 'rescuing' Kairi, so that part of the plan is not yet compromised... But do not shake in your shoes (which are a good ten times bigger then your size I noticed)... Everything is going according to plan...
Ienzo, start the machine... We have a Heartless to build...