fanfiction-star wars:Tomorrow (there'll be more of us) by dimircharmer

Summary:
“FN-2187 was real, right?” She sounds very young again. “Please tell me he was real."

"I'm real,” said Finn, who was on his first patrol since his back healed. “And my name’s Finn now.”

Her eyes widened. “You have a name?

Or: The resistance is starting to get stormtrooper defectors. Finn helps them out.