Batman 1966: What The Fuck Is This?!?

Why does this Batman toy have the head of an adult & the body of a baby? Why are his cape & cowl mismatched? Why is he nude except for pink gloves, booties, & underwear held up by an aquamarine utility belt? Why is the bat symbol tattooed on his chest?
I have no idea!
A great example of a licensed toy (or is it?) before the age of style guides, those company made manuals that told you how a product should look. Oddly enough, this 1966 item from Japan is closer in appearance to T.V. star Adam West than the large majority of American toys of the time.