Duh! A discussion about Catherine? Some mild spoilers ahead!
When I started playing Catherine, I wanted to go at it with answers I felt were honest to me personally. In other words, if I were presented these situations and questions in real life, I would answer the same way. So of course, in the context of Catherine, all my decisions were made with the goal of staying faithful to my current girlfriend.
At first I found it hard to imagine seeing Catherine as anything other than a mysterious temptation. Particularly a temptation that challenges my values and morals. I thought my girlfriend would agree with me to stay with Katherine, Vincent's current girlfriend who wants him to settle down and grow up.
But that's not actually the case. Proving to me that I'm a man and not a woman, she actually gives me an argument as to why I should like her, even from the perspective of a female.
"She's so neutral in the whole message. She just lives life." my girlfriend said. "She's confident, she's carefree, she's forward, [and] she does what she wants without caring about the consequences. Like me"
Certainly at the end of the game, it's made clear that the meter that governs Vincent's state of mind isn't a gauge for black and white morality but rather something more along the lines of Mass Effect's renegade/paragon split. There's nothing really good about choosing the blue side of law and there's nothing really bad about the pink side of chaos. In the end the meter simply represents freedom and order and whether the player prefers life slow and steady or fast and exciting.
As Midnight Venus says, "There's really no right way to climb the tower." And by the end of the game, it's more or less agreeable that the tower represents Vincent's maturation as an adult, leaving behind his comfort zone on the ground floor, forced to make tough decisions in order to reach the top, all while realizing the answer that will ultimately be the reason why Vincent strives so much for the top in the first place.
Of course, it was still a plot that could have still very well killed our protagonist, but that's besides the point of this discussion.
Without delving too deeply on the mystery of just who Catherine is, it's obvious that she is the epitome of a young woman who lives by her feelings and nobody else's. So where does that leave Katherine?
Vincent's situation with Katherine was just a perfect storm of problems. She's feeling pressured by her circle of friends and family to settle down and marry someone which in turn puts the pressure on Vincent, all during a time when Catherine shows up to throw normal decision making out the window.
However, even though we see a lot of Katherine's bossiness contrasting Catherine's free spirit, Katherine does demonstrate that she genuinely cares about Vincent despite how much of a schmuck the game portrays him in the early stages. She texts him letting him know that she worries, she knows how much sugar he likes in his coffee, and she brings him cake! I really saw Katherine as just the adult world Vincent was hesitant to join, but she also represents stability as well. Something Vincent could use after weathering the storm of adulthood.
But my girlfriend doesn't really see it that way.
"I couldn't really sympathize with Katherine. You can't force a guy to date you. I think the relationship was foisted upon him and being the pushover he is, he didn't say anything. And the thought of him losing her was to him a form of leaving his comfort zone."
Of course, we both agree on the metaphor the wall represents, and despite our (well founded) criticism of Vincent as a character early on, we both acknowledge that he makes amazing progress as a person throughout his ordeal.
Between the two of us, it's obvious that the developers were successful in their portrayal of Vincent's possible choices towards adulthood. There really is no right choice towards growing up. It's simply a matter of facing these obstacles head on rather then putting it off or running away from them. And it won't be easy, just like the metaphor of climbing the Tower of Babel. You'll have to scramble over huge blocks, pull heavy stone, avoid a variety of traps, and make many decisions you'll have to live with for the rest of your life.
Catherine really makes you think about how people grow into adults and it forces us to examine what it really means to be in a relationship. It's not as clear cut as being in a monogamous relationship with someone. And despite the zany premise of how it all works as a game, it really comes together to present you with a strong message at the end that few other games can commit to doing.