Ok, I translated this. I'm guessing she's either writing or reading a fanfic, I'm not too familiar with Shoushitsu.

Also, I couldn't think of a good way to translate 致死量 (fatal dose) within context, so fix it as needed.

And his hair is so werjghfa!

Well, this is Shoushitsu Nagato, so my guess is she's venting her massive crush on Kyon via story writing.

Akari said:
I'm guessing she's either writing or reading a fanfic, I'm not too familiar with Shoushitsu.

There's a scene in Vanishing where Kyon asks to borrow the Lit Club room computer, and Yuki lets him, but acts really nervous the whole time he's using it, like he's going to find something she doesn't want him to see.