Jirou can be ... very logical at times. I suppose we'll see, if and when I remember more things.

[At the stare, he shakes his head.He forgets not everyone actually knows swords who got one. That actually is a bit dangerous in his opinion.]

A tachi is a long sword. The standard Japanese sword that people call katana is actually called an uchigatana. They only appeared around the 12th century. Older swords are usually Tachi, long swords. They are also more curved than uchigatanas.