It's almost as though there was some kind of mixup at birth and Amiboshi should have been the 8th Suzaku seishi -- because boy, what an ally he proves to be...

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Full Real Name: Bu Koutoku
Seishi Name: Amiboshi
First Appears: Episode 17 of the anime
Birthplace: Kutou Country, Sanun-shou, Tenryou-shi
Age and Birthday: 15, born August 26
Family: Younger twin brother. His parents were lost in a civil war.
Height: 168cm --> 5'6"
Blood type: B
Seishi Ability: Is able to manipulate with the notes of a flute by sending his ki from his mouth
Hair Color: Blond
Eye Color: Blue

Personality:

From Tasuki no Miko's manga translations, here's what Watase Yuu had to say about Amiboshi:
"Gentle and reserved, but occasionally capable of violent actions. Essentially a kind boy, he is thoughtful and lives only to protect his younger brother. Becomes troubled by his predicament between the Seiryuu and Suzaku Seishi."

Here's what I have to say about that:

Amiboshi's just so caring and devoted it melts my heart. His devotion to those he loves and cares about rivals Tamahome's. He basically raised himself and his twin brother after their parents were killed (and did a pretty impressive job of it, too), and I think he still just likes to look after other people's well-being; hence his attempts at times to comfort Hotohori and Miaka back at the palace (although it can be argued that he had ulterior motives, I still like to think he did it mostly out of the goodness of his heart), and other such occasions.

Essentially, Amoboshi is mature beyond his years, forced to grow up by the circumstances in his life (a common theme in the FY characters)

Older brother, or half of a whole?

The sibling relationship between Amiboshi and Suboshi is... tricky... ^_^; (and, imho, more than a little scary).

The two are identical twins and, like many such twins, share a spiritual and empathetic bond. However, this bond is particularly intense and allows such 'neat' uses such as being able to scratch messages into your arm and have your twin feel it and see the welts on his own arm. I can imagine using this technique to cheat for exams already :).

Also, the twins have a sort of co-dependency between them, which is stronger on Suboshi's side. While you get the feeling that should something happen to Suboshi, Amiboshi would grieve and then move on, should the reverse be the case, Suboshi would, well, crack up. This leads to the question of whether or not the twins could survive without each other, and just how much of individuals are they, anyway?

Could it be that Suboshi is simply an aspect or side of Amiboshi that manifests itself as a whole person, or vice-versa? Hmmmmm...

Anything else?

Having said all that, I really can't think of much else to add here... I really like Amiboshi. He's one of my favorite Seiryuu seishi, next to Soi. He really rocks and I suppose my only wish is that we could have seen more about him in the series.