Abuse Mistake: Calvin is rather clueless. It is a good thing that his brother looks out for him. Or would have been a good thing, if it wasn't for the brother being rather clueless himself - not realize that the advice he's giving amounts to inciting supernatural methods for Domestic Abuse.
Destructive Romance: Ruby is perfect for Calvin. She's a real dream girl, and she would never harm him. Unfortunately, Calvin is not as perfect. He is no perfect dream boy, and the ways in which he can harm her are truly terrifying.
Disappeared Dad: It's implied that Calvin still has not quite gotten over the death of his father.
Gone Horribly Right: Calvin rewrites Ruby to be "miserable without him" and sure enough she soon becomes incredibly clingy and dependant on him, to the point she misses him while he's eating breakfast beside her and has a breakdown on the street because he let go of her hand while they were walking. Once she becomes an emotional wreck he decides to counter this by writing her as being constantly euphoric. Which makes her an insufferably happy individual, who looks like she's about to burst into song any second.
Gratuitous French: For reasons attributable only to indie film quirkiness, the entire soundtrack consists of French songs.
Also, Calvin has Ruby start speaking French to prove to Harry that he created her and he later pulls the same trick to demonstrate the same thing to Ruby herself
Happily Married: Calvin's mom and stepdad seem very happy together. His brother Harry and his wife also seem to have a good marriage, despite some earlier problems.
Heroes Want Redheads: Downplayed: Ruby's hair has red tones, but looks either auburn or brown in different lights.
It's All About Me: There's no denying Calvin is very self absorbed. His ex Lila attempts to call him out this, unintentionally describing most of his relationship problems with Ruby in the process.
Love at First Sight: Double Subverted. When Calvin first sees Ruby in the flesh, he's scared out of his gourd and convinced that he's hallucinating. But when he's convinced that she's not a hallucination (and apologizes to her appropriately for his Freak Out), he's head over heels in love.
Meet Cute: Averted. Ruby's initial manifestation is rife with awkwardness, as she acts like a very confused and concerned girlfriend/roommate, and Calvin acts like it's the beginning of his nervous breakdown.
Mind Rape: The climactic scene, and it is extremely uncomfortable to watch.
Mood Dissonance: The climatic scene, Ruby is barking like a dog, doing sexy dancing, and spinning around while crying her eyes out, and Calvin is in a full A God Am I mode, but is also crying, and the whole thing plays off as a rape scene.
Unsympathetic Comedy Protagonist: Calvin spends the majority of the film being self-absorbed and expecting the relationship to revolve around him. Once Ruby starts expressing the desire for space and her own friends Calvin attempts to start re-writing her into someone more dependant on him.
It's not just Ruby, either, he spends the entire time visiting his mother's house sulking and writing and obviously dislikes his mom's boyfriend.
Wham Line: For Ruby, anyway. "You're not real. I made you up."
What the Hell, Hero?: Lila calls Calvin out on how he actually treated her in their relationship, as opposed to how Calvin views it.