Severus and lily.
This is in no way me trying to rewrite what Rowling did, cause it's awesome, I just wanted to write something that showed Severus and Lily getting together. So here is my attempt, hope someone out there likes it. 

He who must not be named stepped over James' body and stalked towards the door, where on the other side Lily Potter was trying to pile items against it. A futile attempt to protect herself and her infant son. She rushed over and put Harry in his crib. Panic stretched across her face, Harry couldn't die, he just couldn't. A flash and a bang and Lily knew He had blown...