These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
The Subjective Tropes have appeared. It's the killer. Do not die.
Concerning Catherine: is she a malevolent entity who has willingly led several men to their deaths at the behest of Mutton? Or is she merely a Punch Clock Villain who has found someone she genuinely likes in Vincent?
Vincent, Johnny, and Orlando make it pretty clear that they don't want Toby dating Erica, but are they trying to protect Toby from sleeping with a transsexual? Or are they trying to protect Erica from becoming the victim of another hate crime?
Base Breaker: Erica, good God. Many people were riled up by the fact that she is a transsexual and how she's treated.
Katherine also has shades of this, due to some of her actions. Speaking of which, Catherine has shades of it, too...
Disappointing Last Level: The last few stages introduce Random Blocks and Monster Blocks, making the stages less about puzzle-platforming and more about undoing until that next Random Block turns into the block you need.
"Hilarious" might be an overstatement, but some scenes become amusing when looked back on with the knowledge that Catherine is a succubus, and Invisible to Normals:
When Katherine showed up with the cake while Catherine was over, she couldn't have seen Catherine anyway... and when Catherine went into the bathroom, she was probably just eavesdropping from there and waiting for the most inopportune time to flush the toilet.
When Catherine showed up at the Chrono Rabbit while Vincent was there with Katherine, she was probably just hanging out in the entryway, shouting things in Vincent's direction.
It's Hard, so It Sucks: You know something's hard when the masochists that are the Atlus fanbase have so much trouble that Atlus had to patch in an easy mode.
Worse. There are nine stages of climbing, eight of which have these bosses. However, from a certain standpoint, Shadow of Vincent and Thomas Mutton/The Dumuzid are the worst. It's not just their designs that make them scary. In these "boss fights" these two are circling the stairway as Vincent climbs. Not climbing after him, CIRCLING him!! Now, it was bad enough for the poor guy when it had to outclimb the ones chasing him up. The horrible realization sets in that these particular foes are playing with Vincent. And it STILL gets worse!
Not to mention that Shadow of Vincent at one point turns the entire stage pitch-black, save for his creepy-ass grinning mask, and will kill you instantly if you don't climb fast enough. Oh, and then he eats another dream-climber, Steve, right before your eyes.
The Sheepmen. What happens after they die in the dreamworld. The looks on their faces, they even still got the sheep eyes.
One-Scene Wonder: Nergal, Catherine's dad and ruler of the underworld, only shows up in the good and true endings of the cheater's route.
Periphery Demographic: Surprisingly, the game's multiplayer mode has become popular amongst competitive gamers, to the point where in some locales, there is a tournament scene for the game.
The Untwist: Catherine is a succubus. Who honestly didn't see that coming?
Why Would Anyone Take Him Back?: Justified! During the course of the main game, Katherine breaks up with Vincent for pretty justifiable reasons. So, since you can get a Katherine ending, there has to be a good reason why Katherine would ever take Vincent back...and lo and behold, it turns out Catherine was an illusion and Vincent never really cheated. Although it sounds like bullshit at first and Vincent's friends have to back him up for the explanation to stick.