Summer Grass
1. Even in the world of shinobi, her hair and eyes mark her as different. (They're hereditary, no matter what others say.)
2. When she's on her own, she likes saying her full name to herself. (She's afraid she'll forget it otherwise.) She also likes pretending her name means wind.
3. She has no family, at least that's what she's always been told, so she treats her sensei as her father instead. (The sad thing is that the man who leads her to her death is her only surviving relative and he knows it.)
4. As a child, she was often mistaken for a boy. It's an assumption that people still make even after she started wearing her current outfit. (Her habit of binding her chest tightly is probably to blame.)
5. She isn't the first jinchuuriki of the Nanabi. There were two others before her, Nanami the staff-mistress and Ryouta of the Wave. (She cannot live up to either.)
6. At eleven, she has her first crush. The boy's a civilian who she sees in the market helping his parents a lot. She goes home, excited, and tells her sensei all about him. Her sensei reminds her she is a shinobi, a tool for the village to use and that crushes are not part of that. (She never sees the boy again.)
7. People are often confused as to the purpose of the container on her back. They tend to assume that it must aid her in battle somehow and she doesn't bother correcting them. (In actual fact, it's a bunch of scrolls with various bits-and-pieces sealed inside that she's picked up over the years.)
8. Some think that as she's the Nanabi jinchuuriki, she must be the most powerful person in the village. She thinks that's a stupid idea. Obviously the village leader, Hisen-sama, is the strongest, not her. (She hopes it will be her someday though.)
9. Her relationship with the Nanabi is simple. She doesn't use its power any more than necessary and in return, it leaves her alone. (Sometimes it tells her how pathetic she is compared with its previous jinchuuriki though.)
10. She makes genin at ten, chuunin at thirteen and is working towards becoming a jounin at sixteen when the Akatsuki come for her. (Everyone thinks she should have been able to do it faster though.)
11. One of her favourite things to do is window-shopping. She likes looking at the fancy outfits on display and imagining herself in them. (She's never been to a party but she's good at pretending.)
12. Her sensei says she should try wearing white because only good shinobi can manage that without getting their clothes incredibly dirty and it would be an easy way of proving her skill. (He dies the next day and she wears the colour for the first time at his memorial service.)
13. The orphanage takes care of her until she's five when Hisen-sama assigns her a sensei. (The village cannot leave an untrained jinchuuriki without proper supervision.)
14. After her sensei's death, there is a change in the villagers' attitude towards her. Before, they were fairly neutral to her but, now, they openly ignore her. (The change doesn't affect the shinobi though.)
15. Unlike most shinobi, she doesn't carry kunai, shuriken or even senbon. Most people don't realise this, tending to assume that she must store them in the container on her back. (They're partially right, she does use its contents in battle occasionally but they're not conventional weapons at all.)
16. Shibuki is the closest thing she has to a real friend, even if he never treats her the same way again after she switches to her current outfit. One day though, he gives her a hair clip casually. (She still wears it several years later.)
17. The day the Akatsuki come, she's waiting for him to return from a mission. He never forgives himself for not being there. (He's the only one who would have fought for her.)
18. In battle, she doesn't rely on the larger than average chakra reserves that the Nanabi grants her because she sees it as a crutch. (It proves to be her undoing.)
19. Tools can be exchanged for something of greater value if necessary. As she goes to her death, she wonders cynically if she'd been part of a deal. (Hisen trades her for the safety of the village.)
20. Her last thought is that perhaps people were right about her after all. Which people, she's not exactly sure, but someone had to be correct. (Hopefully it's Shibuki and her sensei though.)
Hisen and Shibuki are Taki-nin from the second OAV. Shibuki is Hisen's son. Don't hate Hisen, he had the rest of the village to think about as well.
Nanami was my name for Fuu before hers was revealed and got recycled into being a previous jinchuuriki instead. Ryouta is random though. About the name thing? Using kanji, you can write Fuu in two different ways. The first means seal and the second method, style or wind.
The Shibuki/Fuu thing wrote itself and I'm kind of addicted to the idea now.
And yes, #3 did suggest that she's related to Kakuzu. How exactly, I don't know, but he's old enough that there are lots of possibilities.
The title, by the way, is taken from a haiku by Matsuo Basho (c.1644-1694).