This is an extremely rare authentic original Edo/Meiji Period Shunga woodblock used to produce a multitude of shunga woodblock print artwork.  The first we've actually ever had in store for sale - and perhaps the last!  Not only is the woodblock in excellent condition, but it's also a massive-sized shunga carving - (Oban size (measuring 28.5 cm x 46 cm).  The image shown on paper is on standard B4 size copy paper and not the normal washi paper used for producing woodblock print pictures - which exemplifies the remaining sharpness and intracasies of the carving itself!
 
It's impossible to tell who the original artist was, with albeit the main centrepiece, but from my experience and based on other shunga I've come across over the years, I believe it to be by Yanagawa Shigenobu. 
 
Whoever indeed is the original carver, it is far and rare to come across such fully intact gems nowadays.  If you're drawn to Japanese cultural and erotic history, this piece offers a rare opportunity to own a significant artifact!