4. I love how brutally honest you are
Deeks has never been one to like when people lied to him. He's well aware that there are many types of lies and the ones that are used in order to help someone are often acceptable under everyone's point of view. He doesn't like them. He doesn't even use them.
Sure, he's capable of saying that a shirt looks good on someone when it actually doesn't but he doesn't see that as a lie. It's more like a less painful truth. He doesn't say that it looks good. He says something like 'it could look worse' or 'I've seen people wearing uglier ones'. That's hardly a lie.
But one thing he wants, needs, is someone who is honest with him. Through his life, he has been lied to one too many times.
"Don't worry, honey. Your father will never hurt you." His mother would say when he was just a kid. He believed her because what kind of kid wouldn't believe something his mother said with such a gentle voice? Needless to say that was one of the worst lies of his life.
So he grows up and becomes someone who lies for a living. That's not the accurate description of his job but it works for him.
It becomes more than just a job soon enough. He doesn't go around telling his friends or dates what he does for a living. So he tells a new lie each time and is well aware that the person is talking to is often lying just as badly as he is.
Then he meets Kensi and everything changes. She's different.
He shows up at work one morning, with a yellow shirt that was on the back of his closet, and she frowns as soon as she sees him. "Did you buy that shirt so the bees would mistake you for a flower?"
He thinks she's just mocking him, as usual, so he begins their usual banter without a second thought.
The second time it happens he knows she's not trying to be mean. She's just being honest with him. "Those pants look awful on you." And he never wears them again (he has never liked them in the first place, anyway).
It's part of her personality and he loves it. He knows she will never be anything but honest with him and that gives him a sense of comfort and safety he hasn't felt in a long time. Of course, her honesty goes way beyond his clothes. He has a list of things she has been brutally honest about, a list of quotes she has said to him.
"I don't want to marry you, at least not yet." And it's the truth because she ends up accepting his proposal a few months later.
"I want to have a baby too." And a few months later they find out she's pregnant.
She's brutally honest while talking to him and it means the world to Deeks.