I have written about Buyu names, specifically my own here:
shirotoratiger.proboards.com/index.cgi?board=shihan&action=display&thread=15
"Buyu" means "Martial Friend" which is how we like to view each other. So BUYU names are a fun and almost vital part of acceptance at a dojo.
So let's have some fun figuring out who will be called what!
As well as The Guvnor or Guv I have also been tagged with "The Captain" and "The Psycho" or "Psycho Steve", during my competition years, which I'll write about elsewhere.
I've also been called "Achilles" - after my use of the achilles lock in VT - though I like to tell people it's after Brad Pitt's character in Troy.
I nearly called a version of my dojo The Achilles MA Acadamy, which would have sounded cool.
Shiro Tora was my buyu name at my dojo in Japan when I was the only white fighter there.
That's where that comes from.
To clear up any confucion regarding semantics:
Bu is "martial"
Yu is "friend"
Gu is "name"
To your "Buyu name" is your "Martial Friends name" and your Bugu is your "Martial name". It's the same thing.