(cover by muminika on DeviantArt)
Chell liked to think of herself as a relatively calm, collected person. Which she was, without a shadow of a doubt. She often prided herself in her ability to kick her instinct and emotion to the curb in life or death situations, and, in doing so, she'd ended up where she is now. When (to her luck) a bumbling little robot drops in for a reunion after years of being stranded in space, they find themselves in a situation that none of them had planned out. Now, in a desperate attempt for her forgiveness--all while trying to figure out that interesting, difficult, and tedious little thing called humanity--Wheatley realises there's a lot more to being human than he first thought, and Chell figures out that second chances can make all the difference.
(I don't own Portal or it's characters, Valve does.)