I found these three wordless picture books at our library.  They are all originally European.   If you live in Japan and have a young child, check them out!

The Tree House (De Boomhut by Marije Tolman and Ronald Tolman)  A mysterious and unique Dutch wordless picture book.  Lots of animals in this book.  No real storyline.

The Island (Het Eiland by Marije Tolman and Ronald Tolman)  Very similar to “The Tree House”

The Yellow Balloon (by Charlotte Dematons, don’t what country this book is originally from–the author was born in France with a Belgian dad and Dutch mom)  This wordless book is much more my style than the previous two.  It has lots of little detail, and I find it is easier to discuss this sort of book with a child.  It’s similar to the Anno’s Journey books.