When I write any Japanese text which requires a dash (choonpu: https://en.wikipedia.org/wiki/Ch%C5%8Donpu) or parentheses, the parentheses or dash do not get rendered vertically (i.e. rotated 90 degrees), they only get placed vertically along with the rest of the text.  I am unsure if this is a font issue or something else, but my solution ended up being to put a space in the text, then create a new text object with the characters I wanted, then rotate them 90 degrees. This is not optimal though :P

I've attached an example inkscape svg (with the font used, and the rendered png), which shows the text as it is typed, vs the text as it should be. Hopefully I've made it clear enough :P (OS of svg origin: Linux, Inkscape v. 0.91)

Perhaps the new 'text-orientation' property will solve this. I haven't tried it yet :)