Combining images

[sl60]

   
I wasn't sure exactly what final image you had in mind so I did the following, trying to make it as streamlined as possible. Open the woman image, duplicate it, and double it in size (you don't have to but this makes it easier to work on, at least for me). Open the heart with horns image, duplicate it, make sure the alpha channel is active (Layers to Transparency to Add Alpha Channel), then select the background, delete it, and save as .png (you are making a new .png file). Then open this new heart and horns file with Open as Layers and use the move tool to move it in place. I sized it down a bit (Layer to Scale Image).