I'll use an amazing image as an example. We'll pretend that it's a big scary dragon whose head and neck do not resemble a penis.
Have the head be a separate sprite from the body, be sure you place the pivot point (origin) in a logical spot. [Shown in slide 1]
The head can be drawn over the body. [Shown in slide 2]
You could even put the legs on a separate sprite to animate those as well, or any part of the body. [Shown in slide 3]
Using any art program with layers, you can test how it will look quickly. For actually scripting it:
::Draw Event::CODE
draw_sprite(dragonBody,0,x,y)
draw_sprite(dragonHead,0,x+headOffsetX,y+headOffsetY)
It's a crude example, but I hope it points you in the right direction.