She put a hand on her chin. "That is, until something catastrophic happens. Then they call me to improve security or they hire a bunch of thugs. Depends on the villain."
"You trying to make a point, Nell?"
"Just that you won't be able to go in more than once. The first time could be easy, especially if there are lots of normal people without those mind-blocking helmets. If you get out, then you get out. But the moment you're out, Seer's gonna over compensate for years of shitty security."
"Ah." From Derek's computer room came a high-pitched beep. It wasn't loud, but the nature of the sound assured that he'd be able to hear the alert from anywhere in the house.
"What is that?" Nell asked, nose wrinkled. The beep repeated itself, and Derek saw the girl's nostrils flare in a mix of interest, confusion, and annoyance.
"It's an alert," he replied, and decided that his coffee could wait. He walked as nonchalantly as he could manage back to the source of the sound and sat in his chair. He realized too late that he had neglected to shut the door; Nell had ducked in after him. How had she gotten down from the chair so quickly?
This invasion of his personal space was less endearing and tolerable than her other behaviors, and Derek's patience had been worn thin from days of social interaction. "Get out, girl."
"I want to help," she said defiantly.
Derek was on his feet in an instant. Maybe it was the lack of coffee combined with his exhaustion, but he felt angry. He grabbed her by the neck and pushed her hard so she fell back against the wall with an 'oof' sound and slid down the wall to the floor.
"Fixer, if you want to stay in my house, you do what I tell you. Get the fuck out!"
She obeyed, and scrambled on her hands and knees to the door. She even shut it behind her.