During the second fight with Pinocchio Triela knew that was going to be their last. One way or another, one or both of them was going to die at the other's hands.
There was so much adrenaline going through her body that she didn't even feel the last blow she landed on her. All she saw was her fingers going into his throat and ripping it out. Right before she lost consciousness she saw him hit the floor, and it was then that she knew he was dead.
It wouldn't be until much later that she would know that she'd also survived, and though she was at least happy to still be alive, it occurred to her later that the feeling of victory felt somewhat tainted. It wasn't so much that she felt bad about killing him, rather it was a sort of disappointment. They'd been evenly matched, and now in some way she realized that she'd miss the feeling of having someone to overcome and beat.
And maybe, she later thought to herself, something in her had liked fighting that no-holds-barred beat down with him. He had been the first person to truly make her push herself past her conditioning and enhancements, but now she wasn't sure she had any reason to get any better, and that scared her. He'd opened up something new in her, but now that he was gone she wasn't sure she could go any farther. You could almost call it love, for she really owed him her strength in a sick, twisted sort of way, and she doubted she'd ever fine anyone quite like him again.
She decided not to think too hard about that part. The idea that any love could be like that scared her more than anything else she'd been through with Hillshire. And to be honest, she never wanted anyone – no matter how much they helped her – to replace her Handler's place in her heart, no matter how much it hurt to be with him sometimes.