2x13 Time to Crime

Scotty lies to Lilly about Christina:
Lilly : I hear you went to Christina's bar.
Scotty : Yeah? From who?
Lilly : From her.
Scotty : Me and Nicky went for a couple of beers. Not like we knew she was working there. (...) I ain't interested in your sister, Lil.
Lilly : Good. 'Cause she's a train wreck.
Scotty : Okay.
Lilly : And she didn't hit on you?
Scotty : No.

After Nick Vera strongly recommends him to break it off with Christina, Scotty goes to her :
Scotty : Chris. That night, it was a mistake.
Christina : It was?
Scotty : Cuz.. you know.
Christina : No, I don't know.
Scotty : Your sister... It's ill-advised.
Christina : Scotty, I know what this is. You're thinking about Elisa.
Scotty : I can't be anything with anyone right now. Sorry.
Christina : Well. For the record, I'm not.
Scotty : Look, I don't plan on telling Lil.
Christina : Me neither.
But they end up kissing and Christina is in Scotty's bed in the closing montage.