Leonardo: why didn't you tell me you're seeing someone else?
Penny: you never cared to ask
Penny: besides, you never showed any interest in being exclusive
Leonardo: oh so it's my fault you're a cheater
Penny: we weren't officially a couple
Leonardo: you met my friends
Penny: you should have talked to me instead of assuming things
Leonardo: sorry about that
Leonardo: i gotta go
Penny: Leo, next time just ask me questions
Penny: I'm an open book
Leonardo: I'll try
Penny is seeing someone else. Leonardo thought they were a couple but Penny didn't. Next time Leonardo will ask Penny questions instead of assuming things.