The sudden stop caused Koschei to stumble, barely catching himself before he tumbled to the ground, blinking in confusion as he did, straightening and turning to look at the Doctor, his Theta, unable to mask the hurt as it crossed his face before he was able to wipe it away.
"No? No, what?" Koschei asked, taking a step toward the Doctor, hand outstretched to settle on his shoulder before he thought better of it and let the arm fall limply at his side.
"What did I do this time?" Koschei asked weakly, raising a hand to rub at the back of his neck nervously. The Doctor had been mad at him before, leaving Koschei had been clueless about the reason or the cause. He couldn't help but worry that that was what this was. But he couldn't even fathom what it could be this time.