Ikea has a new range of fabric with a manga kinda theme (well, nobody said you couldn't combine manga and vikings...!!). The Charlotta fabrics are designed by Åsa Ekström.
This is Charlotta Teckning:
and this is Charlotta Block:
which as you can see is darker in colour - the range has lighter and darker black and white fabrics in it.
See the whole range here; $8.99/metre, 150cm wide, and pay attention to the repeat if you're sewing it into curtains.
But what's to stop you stapling some over a cheap canvas frame for a wall feature? Or make three, for greater impact? Maybe they could highlight your collection of graphic novels and manga and so forth?
If you're after manga in colour, the quilt fabric manufacturer Alexander Henry (that's the manufacturer website, you would buy from a retailer such as the link given below) often has unusual fabrics, including this one from their Indochine range:
which is available from this online retailer (where I found this image). $US9.50/yard, 45in/112cm wide.