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Yeah, in a direction you don't want it.
Could also be some kind of fender, but ideally it goed a bit more backwards to keep your back dry.
Also, to make it easier to convert it to a URT-style suspension frame.
Pure aesthetics, I think, as often on san-Rensho (don't say "three rensho"!).

why in the direcction ytou dont want it?

also has a couple of extra small tubes in the BB shell, joining the down tube, I suppose also for more rigidity