Foe Yay: Kyle and Bradley. Let's put it this way: If the only thing changed in the entire game was Bradley's gender, and the entire rest of the game was kept completely unchanged... the thing would be immediately classified as a totally straight, heterosexual chasing-the-lost-love-interest story.
More Homoerotic Subtext than Foe Yay, really. Brian tells Kyle in his letter that he harbours absolutely no ill will against Kyle despite the fact that Kyle shot him, and Kyle states straight out to Ed that he doesn't hate Brian, that chasing Brian has nothing to do with revenge. He just wants to understand. Besides, let's recap the pre-game events:
Kyle quits his job as a respected police officer, essentially throwing away his entire (and very promising) career, because it was getting in the way of finding Brian Bradley. Granted, his superiors were probably going to fire him anyway... over not doing his job any more due to spending all of his time hunting down his erstwhile partner.
He has spent every waking moment of the three years before the game doing essentially nothing but following up any leads that might lead him to Brian. He took the job he has partially because it would allow him to move around quite a bit, making his hunt easier.
On top of all of that, he's in almost exact same position as Kevin Woodward. Partner made some shady deals to protect someone they loved? Check. Accused his partner without giving them a chance to explain? Check. Drove his partner away? Check. (Granted, Kevin did it with words and Kyle did it with a bullet, but still.) Regrets it horribly and desperately wants to hear his partner's side of the story? Check. Threw away his successful career and gave up everything just to find his missing partner? Check. Driven to the bottle just to deal with the loss? Check. It's hard to imagine that the writers missed the glaring parallels.
Kyle: "The taste of gin and vermouth lingers on my lips, the only kiss I've known in years. And then I hear Bradley's voice in my head..."
Magnificent Bastard: Brian Bradley betrayed the NYPD to work for the crime syndicate, NILE, after they kidnapped his sister. Deciding to betray NILE after he feels sympathy for a man whose daughter they kidnapped, Bradley murders one of his criminal associates and steals the "Angel Opening the Door" painting from them. Surviving being shot by his former NYPD partner, Kyle Hyde, who discovers his criminal ties, Bradley goes to Hotel Dusk, where he leaves clues for Kyle to track him down. When Kyle solves the mystery Bradley left for him, Bradley cordially bids him farewell, leaving to continue chasing the NILE members who killed his sister.
Nightmare Fuel: The game slips into a darker territory towards the end of chapter 9 when Kyle finds Louie lying on the ground in the hotel's wine cellar and when he gets closer, a figure with a sack over his head sneaks up behind him and hits him in the back of his head with a bottle. A bit later, Kyle, Louie and Rosa find out that the hotel has a secret basement, which is quite eerie by itself, but when Kyle investigates a room in it, he suddenly hears footsteps and the door shutting behind him, leaving him in an airtight room with no one close enough to hear him hitting the door. If you don't solve the room's puzzle in time, which youprobably won't, Kyle dies of suffocation. Thankfully his confrontation with Dunning afterwards implies the latter didn't know Kyle was there.
Paranoia Fuel: By around Chapter 2 or 3, you will be worried about running into/getting kicked out by Dunning everywhere.
At one point the game over music plays but the player won't get a game over. This happens when playing the Side A of Iris' tape.
At another point Dunning catches Kyle investigating his room. The usual dialogue before getting a game over happens but the usual music doesn't play. Turns out it's required and doesn't give an actual game over.
Scrappy Mechanic: Hoo boy, the interrogations. For one, giving a wrong response can cause you to fail the sequence, and starting again means skipping large amounts of text. Also, even if you know what you just said was wrong, you still have to finish asking all other questions before you can restart. And finally, you can't save your game during these moments.
Ship Tease: Exponentially increased between Kyle and Rachel.
Mila. Oh God, Mila. Witnesses her friend get kidnapped by a complete stranger at the age of nine, brutally struck by said person and put into a coma, wakes up ten years later as a mute, searches for her father for six months with no sense of direction, and passes out again in the same room where her friend was kidnapped this time losing her breath and narrowly pulled back from the edge. And for all of her trouble, what does she learn? That her father may have been killed by Kyle's partner in the heat of rage when he came to visit her, as revenge for killing his own sister whose name was also Mila. Poor girl. For all of the crap she went through, there's no argument that she deserved a happy ending, either with Kyle or Rosa.
By contrast, most of Kyle's deadpan snarking were Lost in Translation to the French version, in which the furniture-clicking comments are even more generic and boring; however, it has Louie call Melissa by the cutesy nickname "Meli-Melo" as he picks her up to carry her back to her room, making the already heartwarming scene just unbearably adorable.