Ziva frowned down at the book in her lap. She had been reading the same sentence for the third time now and it was all Tim's fault. She could feel him staring at her, watching her and he had been doing it for a few minutes now. She was getting unnerved. He hadn't said anything but there was something very disturbing about that silence, and she was coming up with a dozen bad scenarios that would have him watch her intensely like that.

"Doing some character studying again, McGee?" she asked him, aware of her use of his surname, even though they were at home and alone. Tim noticed, too, she saw him flinch out of the corner of her eye when she turned the page. Ziva quickly hid a smirk before looking at him.

"Um, no?" he tried and she narrowed her eyes at him.

"Then why have you been watching me for the better part of half an hour now?" she asked him, closing her book and angling her body so she was facing him on the couch. Jethro raised his head and slowly stood, trotting over to her and nudging her knee with his snout. Ziva reached down to run her hand through the dog's fur, appreciating that Tim had taught him that humans reading meant that he wouldn't get played with or patted, even if he came begging. Though Ziva doubted that Jethro was just after getting some affection. He seemed to be good at sensing tension in her or between her and Tim and would follow her everywhere in those moments. She supposed it was a side-effect of having lived with Tim for years now, that the dog had started to pick up on his mood and realized that when he decided to get goofy or cuddly, he could cheer his master up, and now decided that the same was true for Ziva.

"I like watching you." Tim shrugged and Ziva gave him a look. "What?"

"Now you're starting to sound creepy." she shook her head, pointing at Tim and snapping her fingers, hoping it would send the dog his way. Jethro just sat back and looked at her before giving a short bark and placing his head firmly in her lap. Ziva gave a soft groan and admitted defeat, starting to scratch the dog in earnest. She'd have preferred to watch Tim when he answered but someone apparently decided that this wasn't happening.

"Sorry." Tim apologized, walking over to her and sitting down next to her, again watching her. Ziva turned her head and he blinked, sighing. "I was thinking about what Ryan said." he told her, frowning down at the dog when Jethro began to drool over her jeans.

"About what?" Ziva asked her boyfriend, turning her attention from the dog.

"Tells, in general." he shrugged. "When we were in the bullpen, I noticed that she was playing with her necklace and it struck me as an odd thing, for someone working in PsyOps to have such an obvious tell. And then I got thinking about what mine are, and when I realized that you probably knew all of them I suddenly found that I had no idea what yours were."

Ziva blinked in surprise, feeling Jethro leave her in favor of going to the kitchen where his food and water were.

"Who says I have tells?" she tried, but Tim merely continued to watch her and Ziva sighed, shaking her head. "Okay, stupid question." she breathed, running her hand through her hair. "Well, I can assure you know a few very obvious tells of mine."

"Yeah? Like what?"

"Like, my English gets worse when I am agitated." Ziva supplied and Tim tried to bite back a grin. She rolled her eyes at him, frowning. "The others I try to suppress."

"Why?" he asked her, tilting his head. Ziva gave a soft sigh.

"Force of habit." she shrugged. "But there are a few universal ones, not making eye contact, touching jewelry…"

"You toy with your earrings." Tim suddenly supplied. "Though I have no idea why."

Ziva shrugged. "See, you know one."

"One. How many do I have that you know of?" Tim asked, suddenly sounding defeated. Ziva considered deflecting before deciding to aim low instead.

"A couple." she shrugged. At Tim's incredulous look, she gave him another shrug. "You blush like a teenager sometimes. Your voice goes up when you're embarrassed. When something annoys you, you raise one of your eyebrows. Those are universal tells pretty much everyone has."

"How come I rarely see them with you?"

Ziva closed her eyes to keep herself from making a sharp remark.

"Mossad officers who cannot suppress obvious reactions to things rarely last long." she reminded him with a raised eyebrow. Tim swallowed visibly and reached for her hand.

"I'm sorry, I didn't..." he muttered, shaking his head. "I'm really sorry, Ziva."

She gave a soft sigh and shook her head, entwining their fingers.

"I am not angry, it's just… not something I like to talk about. And for the record, the only time I actively try to suppress them is when we are on the job, especially when talking to witnesses and possible suspects." she told him, staring at their hands.

"Ziva?" Tim called her name softly and she looked at him, giving him a gentle smile. He opened his mouth to say something but then shook his head.

"Does Gibbs have a tell?" he asked her instead and Ziva frowned.

"You mean, besides yelling at people or glaring at them?" she asked, making him chuckle.

"Yeah, stupid question." he grinned, leaning in to kiss her.