How would you describe wings sprouting out of a girl''s back?

Is it painful or beautiful? That's what's really important.

If it's painful you can describe the warm feeling of blood trickling down her back. The ripping feeling as her skin tore apart. Her passing out or falling to the floor from the excruciating pain.

Too graphic? Well then you can make it beautiful. Wings fluttering outwards reaching to the sky. The soft touch of the feathers against her skin. Feeling reborn as the wings bursted from her back.

It really depends on the book you're writing. If she's an angel I'd go with the second if she's an experiment or a monster of some sort I'd go with the first.

Sensory adjectives are important in describing any scene. Close your eyes and picture the moment in your head. As the author, you are the only one who knows exactly what is happening in this scene. Is she outside? What is the weather like? Is it day or night? Is she in pain? What look is on her face? How is the rest of her body responding? Are her muscles contracting? Is there blood? Does she seem empowered? What is the scent in the room? All of these small details will make for a wonderfully described scene.

This is where the vocabulary words you thought you would never need come in handy.
This is also why you should take time out to describe thing poetically to get into the habit.

Odd, but it attracts me because it makes her special. and she can fly, so.

A hen's feathers?

Sorry to you girls. In my language, German, a hen is a girl, and it's not always meant in a derogative way, although sometimes it can be.

Angela Carter did it quite convincingly in 'Nights at the Circus'.

Angelic