I assumed it was a fake GBA clone at first, which is what it would seem the people designing the box and instruction manual also assumed given the imagery they used....but we'll get onto that.

It's actually a portable famicom that plays carts through a convoluted adaptor that plugs into the device and forms a bridge between the tiny cart slot and the cart
It should look like the thing on the left here:

....this is where my problem began.
It duly arrived in it's hilariously and infamously badly translated box (and a box that had quite obviously spent some time in flatpacked form). However, upon opening it I found only the console and the TV adaptor inside. No special yellow cartridge to act as a bridge between the weird device and a famicom cart. In essence then all I can do with it is turn it on and watch wavy lines go up and down the screen (I don't even know if this means it's working or not)

The way that the box was shaped leads me to believe it's sat in a warehouse somewhere flatpacked and someone has just tossed in the parts they though belonged there. I've emailed the seller but I'm not convinced he knows that it should come with a connector cart. This is the listing which mentions something about "foreign return stock".
http://item.taobao.com/item.htm?_u=q2689tqe3243&id=27050256107
Another Taoaboer is selling these even cheaper but his pictures also don't show any cart adaptor with it? The front of the box shows a deformed looking "Game Boy Advance" cart and the manual confuses things further by neglecting any mention of the adaptor and also indicating a cart should be inserted:

The company who made this device was well named because everything about it is a mystery. The shell clearly tries to convince people it is a GBA, the box art does the same, the instruction manual gives impossible instructions and the adaptor is mentioned nowhere in any of the material? Who was this marketed at and how was anybody supposed to know what it was for on its release? It's as if nobody involved in the design or production of this thing communicated with each other in any way during its creation, or it's purpose was radically altered halfway through it's manufacturing.
Anyway, unless the taobao seller has just made a mistake I now have an entirely useless conversation piece. Does anyone know where I might source on of these yellow adaptors from?