Need help on making a spoiler image.

I’m using inkscape for your information.
 
I am having a lot of trouble trying to make this spoiler image.
 
I tried using this image  
 
and this image  
 
to use as a template for my spoiler image, but I don’t know how to get my transparent pony picture to not look like it was pasted onto a square. And when I export it as a PNG, it always looks like this image  
But I want the pony picture to blend in with the template like this image:  
 
Help will be appreciated.

@StrangeGirl
 
Tried using a soft eraser brush of some sort on the edges?
 
 
Oh…  
And blender brush. Don’t forget the blender brush.  
And blurring c:

@Stooped_hooy  
I’ll see what I can do.

@StrangeGirl
 
Oh. Missed your link.  
Haven’t used inkscape but in other programs like SAI, PS, Painter there are layer settings like combine, multiply, etc.  
They might do something if you experiment with them. Rarely used them myself.
 
And you can use template layer, slap your pone on it, then dublicate template layer, move it over your pone layer and use eraser on dublicate layer to make pone visible and seemingly blend with a template.
 
Also, you can just look for transparent pony vector.

@Stooped_hooy  
I finished it. I know it’s not the best, but thanks for the help.  
>>1598572t (merged)

@StrangeGirl
 
Glad to be of help.  
Looks nice even though I never use spoilers xD