Thanks for the suggestions. However, some of them didn't really seem to fit the one that what I've been looking for.
When, I say a suit, I mean this:
Or Saber's outfit from Fate/zero.
But I'll consider Sun Ken Rock, Kandachime and those shows that MisaoFan suggested. I'm already reading Gangsta and I really love Nicholas since he's so badass.
For Scanner's suggestions..........uh, close enough but, in Karas (which I've seen one episode and put it on hold), the characters who are wielding swords are in
armor suits, not business suits. Samurai 7 (which I've finished before) and Bakumatsu almost fit the description. In Sacred Blacksmith, the male lead's outfit is medieval and not very close to the description.
But again, thanks to the description.