The teleportation and jumping dimensions is new, as are a few other powers, and Rian's described being able to see new things that others can't. Rian also has a type of bloodline known as a dojutsu (an eye technique), which seems to enable that.

Nope. His clan got into the occasional fight with the Yamanaka, but they weren't able to reverse engineer anything usable of the mental techniques.

"Magic eye bullshit" is "eye technique" and a type of bloodline? She can see the relevance of seeing things to eyes, but in what way does teleportation and such connect? (What things does she see?)

It's vague, Rian's more open with how her techniques work than most, but she's not giving out functional details and seems to mostly be working on intuition anyways. And yeah the magic eye bullshit is her bloodline. Most people don't call it that, it's the Rinnegan officially, but it's bullshit.

Why so?

Eye techniques don't give the number of powers she describes usually? They tend to do one or two things. The Hyuuga can see chakra, including through walls. The Uchiha can usually - he's not positive how base sharingan works but it definitely allows seeing things in slow motion and perfect memory. Things like that.

Understood. 

And, she's been keeping aware, has the person she is attempting to trade with arrived yet?

Yup, entering right now in fact.

She excuses herself. Does this seem a good time to approach?

Possibly. There's no one talking to her trade partner, who's meandering over to the cafeteria line.

Waiting until she's taken her food.

She does, sitting down off on her own a bit, and glancing up when L approaches.

"Oh, hey," she says.

"Hello. May I? Or shall I wait until after dinner?"

"Go ahead, now's as good a time as any."

She sits. Will the other begin the conversation, or will this be to her?

"I've got the clothes you wanted for working on in my bag," she says off-handedly. "Do you know the specifics yet you'd like out of a tool-set?"

She describes what she needs. 

She listens attentively, nodding. "Alright. I don't have many specifications on the clothes, except..." And she can describe things like minimum and maximum temperatures.

This is useful. She asks some questions.

"The most usual way to do this involves embroidery on the clothes - not very much, and it can be worked less noticeably if desired. Would this be acceptable?"

"Oh, that's fine. I don't mind at all. Are there pattern limitations?"

"The base purpose is magical symbols. They can be worked more elaborately -" she illusions some examples, "but I'm not a craftsperson myself."

"Aha. Well, these are my work clothes, so I'm really not picky about what they look like; whatever seems reasonable to you?"

"Understood. If it matters to you what sort of thread and such I use it would be helpful if you could supply it; otherwise I will use what I can obtain."

"I don't care, but I can point you towards where to get thread..."

"That would be very helpful, thank you. And a needle, if possible." If not she can make do, but it would certainly be both easier and simpler.

"Yeah, I know one of the seamstresses, should be easy enough to get some spare."