It was what he wanted to say. He wanted to shout it, to use the word as a springboard, launch himself at Dark, rip him open, destroy the facade of the boy and return the man, rip open the man and find the being within, tear him apart, turn him to dust, turn everything that belonged to him to ashes and show him just how little he owned Loki, prove to him that the only one who controlled Loki was Loki.
Except he was certain he would never be able to accomplish this. If Dark could keep him from speaking words that led to others finding him out, even alone, then what else could he be made to do? What else, if prompted, would Dark do with him?
He'd fought it off, once. He'd had Darcy, Emma, Needy - friends and people who had been concerned enough to come to his aid, talk him out of his own mind and get him aware enough to tear every last scrap of the lingering shadow from himself.
Or, so he'd thought. Really, what had he done? Bought himself more time? Lured himself into a false sense of security, thinking he could handle anything? Led the others to trust him, so that now - back outside himself - he would lead them to their eventual destruction at his hands?
He did not even have control over his own words; what else could Dark do, on a whim?
"I will not," he responded - a moment late, less rage and fire and more resigned, veiled panic laced through with the bitter indignation of the proud in chains. "I will go nowhere with you." I will find a way out, he did not say; instead, "You will release me," and for all that he appeared an offended prince-godling, all regal power and stony facade, he knew with a twist in his chest that Dark could see straight through all of that, see the churning sickening dark fear and ice and rage inside, all that made him who he was (would someday make him who he was trying not to be, twisted parody of this Loki).