The attraction that Slan, the female member of the Godhand, has to Guts from Berserk. Given that she's a sadistic demonic god, she basically derives a lot of pleasure from all the suffering she and the other God Hands can put him through. And it's not exactly helped by the fact that Slan is Too Kinky to Torture — the only thing Guts succeeds in doing by impaling and blowing off half of Slan's torso with his Arm Cannon during his battle with her in the Qliphoth is giving her an orgasm.
Bleach: There is a very twisted straight example in the warped relationship between former 3rd Espada Nel Tu and 5th Espada Nnoitra Jiruga. Nel's constant attempts at saving Nnoitra, coupled with the fact that Nnoitra, no matter what he does, cannot seem to get her out of his head don't help.
Orihime has had quite a bit of subtextual Foe Yay shipping going on, mostly with Ulquiorra and Grimmjow, but there's even a little with Aizen too.
Busou Renkin: Papillon's obsession with Kazuki. Magnified by the fact that there's already a lot of subtext around Papillon with his flamboyant outfit including speedos and a distinctive butterfly mask.
Chrono Crusade has Aion/Chrono. In the manga, Aion is really Chrono's twin brother, unknown to him, and actually cares quite a bit for Chrono. The anime adaptation also included a scene where Aion holds Chrono's face in his hands and leans so close while speaking to him that their lips are almost touching. He also has a bit of In Love with Your Carnage for Chrono in both versions.
This defines the relationship between Rally Vincent and the Big Bad Goldie Musou in Gunsmith Cats manga, even though it's decidedly one-sided, with Goldie's desire to possess Rally, body and soul is the main reason for their conflict. There's also some Foe Yay between Rally and the Jerk with a Heart of Gold rival/enemy/ally Bean Bandit.
To a lesser degree, also the relationship between Goldie and Rally's junior sidekick Misty Brown. In one scene Misty drugged senseless in her underwear, in the next Misty in leather bondage gear, crying. Cue Squick. And in the last book of the series the two end up in a consensual relationship! Seriously!
Heavy Metal L Gaim: Lampshaded by The Hero Daba Myroad in chapter 15, as seen in the quote above. Unknown Rival Gablet's became so driven and so obsessive with defeating Daba that sometimes it sounded like if he had a crush on him.
Kemono no Souja Erin: Damiya becomes suddenly very touchy-feely with Erin, when it turns out that she can control the beast lords. During their first meeting one-on-one he grabs her hand, gets very close with her and compliments her eyes. Unsurprisingly, when they are interrupted by his aunt, she assumes that he tries to force himself on her. He also seems to be impressed, when Erin doesnít buy his sweet talk and is overly fascinated by her ability, even comparing her to Je, when she rides on Lilan to rescue the queen.
Soubi with two of the main villains from Loveless One being Ritsu-sensei in which they actually were sort of in a relationship. (Ritsu took his ears) and Soubi was upset when Ritsu gave him to Semei. But currently they're both just sort of neutral to each other now. And, of course, Semei. With Soubi's obsession to obey the man's every word, despite the fact that he purposefully abandoned him. And replaced him with his real Beloved fighter Nisei. However, Soubi's obsession could be because of the way he was trained and nothing more.
Ritsuka and Semei. Though Semei doesn't see Ritsuka as his enemy, Ritsuka is kind of torn on what Semei is, exactly, due to what people have told him about him and many unanswered questions. Such as why he faked his death.
Tabool in Now and Then, Here and There is unhealthily obsessed with garnering any attention whatsoever from his best-friend-turned-rival, Nabuca, to the point that he gets jealous of a freaking six-year-old. Long story short: Nabuca continues to reject Tabool and it does not end well.
Phi Brain Kami No Puzzle gives us Rook and Kaito. The two were childhood friends. Unfortunately, Rook was taken away as a child and eventually became a Tyke Bomb who determined that Kaito was the perfect candidate for Phi Brain, a program filled with Death Trap puzzles, the ultimate goal of which is to create the perfect puzzle solver. It Makes Sense in Context. As Kaito solves puzzles, Rook gushes over how beautiful he is when doing so. He even concocts a plan to convince Kaito that the best thing to do is to leave his True Companions behind and join him. It doesn't work. He gets very angry when Kaito's Love Interest, Nonoha, displays how close she and Kaito are. When Kaito finally makes it clear that he will never join POG, the conglomerate Rook works for, Rook goes into a mad rage, screaming that Kaito is his and that he has to join him. Rook's personal Dragon needs to hold him back from making a grab at Kaito himself.
In one episode of Sonic X, during a fighting tournament, Rouge fights Tails and beats him... by kissing him. A few episodes earlier, she essentially flirts with Knuckles. Worse yet, the latter relationship is canon.
Good lord, do Akagi and Uozumi have this in Slam Dunk. It's been mentioned that Uozumi talks about defeating Akagi everyday and from what we've seen, this is probably not an exaggeration. He almost instantly took an interest in Akagi when he first saw him, cheered him on during the Kainan game, and his rivalry with him is his main motivation for improving. Even after quitting basketball he still travels all the way to Hiroshima just to see Akagi play and even gives him advice in the middle of a game. On Akagi's side he considers Uozumi the better player (despite what everyone else says) and has a great deal of respect for him. Their bromance is even mocked at times, such as when they hug and cry on each other's shoulder, only to show that they're both far too ugly for this to be anything but fan disservice.
Ayeka and Ryoko from Tenchi Muyo! Depending on which Alternate Continuity you choose, they are old childhood acquaintances or mortal enemies, but they always fight — and not just over Tenchi's affections. In at least one alternate world glimpsed during an Alternate Universe episode of the television series, though, they are clearly in a relationship with each other. Though outside forces were involved.
In the Seinen manga Wolf Guy - Wolfen Crest, there's the Big Bad Haguro Dou, who is the young son of a powerful Yakuza boss, and who becomes completely and crazily obsessed with protagonist (and werewolf) Inugami. He initially doesn't care about or even think twice about Inugami... until he pushes Inugami too far. Which results in Inugami showing him his true form and scaring the shit out of Haguro. Haguro goes insane from it, and obsesses and stalks Inugami after that, even cutting himself all over his arm and carving the word "Inu" onto his hand. And yes, it's creepy to the point of being something of a sexual obsession as well - Haguro has been shown after that to, while having sex with his (equally crazy) girlfriend Ryuuko (who, by the way, also lusts after Inugami and thinks about him while having sex with Haguro), think only about Inugami, and pretty much screams his name while imagining him. Later, Haguro even ends up raping his male subordinate to death, while again thinking of Inugami. And after Inugami decides he's had enough of this shit and tries to move away, Haguro, being the stalker he is, tries desperately to do stuff to piss Inugami off so that he'll come back.
Haguro is damn near the epitome of this trope. Having violent sex with his girlfriend Ryuuko and having an orgasm while screaming Inugami's name? Buttraping the hell out of his male subordinate while, again, thinking about Inugami and how this is a punishment for him? Brutally raping Aoshika while recording it so that Inugami can see, practically talking to the camera (and, therefore, to Inugami) through the entire thing so that Inugami will come back to him? The only thing that's missing is for Haguro to actually try to rape Inugami himself, and pretty sure he's working on that one as well.
Zero no Tsukaima: In the fourth season's OP, Louise gets licked on her face by a new, evil purple-haired girl named Janette and the girl hugs Louise close to her with a blushing Louise struggling to get away. And in episode two Janette tricks Louise by pretending to be a plebeian, gets close to her face, and licks her again. She also touches her face and says that if things had worked out different they could have been friends. She also calls Louise "cute and innocent".
Naruto: It's been stated that the sharingan awakens with the loss of a loved one. Madara Uchiha awoke his sharingan when he ended his friendship with Hashirama Senju, who would eventually become (though reluctantly) his Arch-Enemy.
The Joker often makes comments toward Batman of this nature, talking about their relationship as though it were romantic, and making flirtatious advances. It's not clear if this is out of some actual attraction or simply to make Batman uncomfortable. To say nothing of how in Arkham Asylum: A Serious House on Serious Earth he actually slaps Batman's ass.
in Nth Man: The Ultimate Ninja , a flirtatious relationship gradually develops between the American ninja John Doe and the Soviet KGB leader Colonel Novikova... to the consternation of their subordinates and comrades.
Bond/Le Chiffre from Casino Royale (2006). When your naked torture scene begins with the villain eyeing Bond up and saying "You've taken good care of your body"... This is actually more explicit in the novel where Le Chiffre addresses Bond as "dear boy" during the scene and of course, is the fact that Fleming based him on the bisexual Alastair Crowley. It's also worth noting that the idea of Le Chiffre having a girlfriend is movie-only (the original liked to patronize the string of brothels that he owned).
Skyfall throws "implications" right out the window with Silva's opening scene, where Bond is tied to a chair and Silva unbuttons his shirt to touch a scar on Bond's shoulder, continues to caress his throat, and strokes Bond's thighs. Bond responds to Silva's quiet snark, "Well...first time for everything, yes?" with, "What makes you think this is my first time?"
Craig's Bond is not the first to have subtext with the villain — there was an amount of homoeroticism between Bond and Alec in Golden Eye.
Alec: "James and I used to share everything...absolutely everything"
While Xerxes, as portrayed in 300, appears to be into everything, and his feelings were not reciprocated, his interest in Leonidas certainly appeared to be more than political. The director felt that the teenage boy demographic would find Xerxes scarier if he was presented as a Depraved Homosexual intent on molesting the protagonist. Unfortunate Implications ahoy!
Roxy/Velma from Chicago. Even besides the whole Girls Behind Bars aspect of it, Roxy and Velma do spend a lot of time glaring at each other while wearing nothing but skimpy underwear. And during the last number they seem... a lot more friendly.
There is a strong albeit disturbed vibe from Hannibal Lector towards Will Graham in Red Dragon.
Clever boy. I think I'll eat your heart.
In Scanners II The New Order, The Dragon Peter Drak makes a point of repeatedly referring to protagonist David Kellum as a "pretty boy", "Davie", and commenting on his "pretty eyes".
Fight Club. Aside from the fact that they're basically the same person, there's a large amount of subtext between The Narrator and Tyler, as Tyler is the epitome of everything the Narrator wishes he were, compared to the Narrator's docile, repressed sexuality. The movie opens with Tyler shoving the barrel of a gun down the Narrator's throat, they live together, bathe together, spend their nights beating each other to a pulp while shirtless and covered in sweat, and let's not forget the chemical burn scene, in which Tyler kisses the Narrator's hand and holds him down while he burns him, and Marla's almost jealous reaction when she sees the scar ("Who did that to you? Guy or girl?"). There's also the Narrator's jealousy and subsequent brutal beat-down of the pretty blond guy who started to seem like Tyler's new favorite.
X-Men: First Class: Erik with Charles, to the point where Television Without Pity gave them the "Best Couple" award. Also present in the original X-Men Trilogy. It's supported both by James Mc Avoy (who plays Xavier in First Class) and Ian Mc Kellen (who plays Magneto in the other films). A bit of a variation on this trope in that they're actually friends despite their opposing goals and the subtext comes from the friendship rather than hostility.
Deliberately inferred in the original The Hitcher, to the point where it creeps out the cops to watch the lead characters interact in the interrogation room.
Hrathen towards Sarene, in Elantris. Later turns from subtext to Love Epiphany, although the latter character remains totally oblivious to any of this.
There's also that phone call in The Sound of Drums where the Doctor says all they have is each other.
Just as in Red Dragon, there's quite a bit of this between Hannibal Lecter and Will Graham on Hannibal.
Murdoch Mysteries: James Gillies, the criminal mastermind on the show, kisses Detective William Murdoch on the mouth for a full three seconds towards the end of "Midnight Train to Kingston."
Gillies: For the last time, this is it for us. Doesn't that make you just... a little bit sad?
Gillies: Not even a teensy bit?
Murdoch: [shakes his head]
Gillies: Come now, Detective. You and I share something, something... special. I'll miss you, you know that. [grabs Murdoch by the collar and kisses him]
Sherlock: Primary antagonist Jim Moriarty loves flirting with Sherlock, even pretending to be gay and giving him his number in one episode.
Lex Luthor and Clark Kent on Smallville may be the epitome of this trope in distilled form.
Some of the original comics support this interpretation; notably, the Silver Age story where Superboy keeps a trophy room of mementos of Luthor before he turned evil, including some of his lost hair. Note that before he turned evil, Lex likewise had a Superboy room.
Via genetic engineering, they basically have a son together, Alexander Luthor/Conner Kent.
Clark has it with both incarnations of Zod, too. (It didn't help that the first was borrowing Lex's body for their final battle.)
Lois Lane and Tess Mercer on Smallville. Exhibit A:
Lois: What is it with you and physical violence?
Tess: The last time you and I saw each other, things did get a little... physical, didn't they? *wiggles her shoulders suggestively*
Lois: And then what happened, Tess? Inquiring minds want to know.
Tess: You don't remember?
Lois: Well, a three-week concussion can do that to you. But I think that you bonked me on the head and then held me somewhere.
Tess: Held you? That's wishful thinking, Lane. When I came to, you were already gone. We never did get to finish what we started, though. Little rematch?
Another time, she said she missed the French maid outfit Lois had once disguised herself in. It'd be easier to list the scenes with the two of them that don't scream "For the love of Rao, just make out already!"
Chloe Sullivan and Lionel Luthor. This one is canonical (from Lionel's end, anyway; they actually had an Almost Kiss, but Lionel was in Clark's body), at least according to Word Of God, since John Glover, the actor who played Lionel, actually said he was putting attraction to Chloe into his portrayal of the character. You can see for yourself here.
The Megas, a Mega Man fan band, have the song "Blue Like You" about Flash Man feeling this for Mega Man.
Played for Laughs in the fifth and final season of Bleak Expectations, where it becomes increasingly obvious to Ripely that her husband and the evil Mr Benevolent do have a romantic relationship.
Ripely: Oh, look. It's your boyfriend.
Dota 2 exemplifies this on, of all people, Tidehunter and Kunkka. They are established in their backstories as hating each other - Tidehunter's hatred for Kunkka is never explained though, but out of that hatred he sunk his beloved ship. Those are some of the responses they have to each other:
Kunkka: I never tire of hearing my name on your lips.
Kunkka: Ah, nobody hated me like Tidehunter. He made me feel appreciated.
Kunkka: Ah, Tidehunter, you cared enough to hate me. You can't buy that sort of love.
Sonic the Hedgehog: Here we have Knuckles and Rouge, particularly in 'Sonic Adventure 2''. The two spend the better part of the game at each other's throat, mainly because they both want to restore the Master Emerald after it as broken earlier, albeit for different reasons, noble and selfish respectively. However, in their final confrontation when Rouge was in trouble, Knuckles saved her and the two gazed in each other's eyes while holding hands for a good few seconds before Rouge pulled away in disgust. Knuckles calls her out on her ungrateful attitude, but then Rouge teases that he just wanted to hold her hand. Rouge decides to just give up her pieces and leaves it at that, Knuckles apologizes if he hurt her in their previous fight and Rouge gives a small smile in his direction before departing.
League of Legends: Garen and Katarina, both paragons of diametrically opposed city states. They received high compatibility ratings under Blitzcrank's matchmaking service but aren't an official couple. During the game, Garen has unique jokes specifically toward Katarina, which are somewhat flirty.
Sluggy Freelance: In the story "Girls' Night Out", a series of random events leads the main characters to get tangled with a minor, animal-obsessedDiabolical Mastermind called Tadius Greasenherr, and ZoŽ having to bluff him that she's a fellow criminal boss called Cacamille to save the others. As soon as she's away from his sight, though, she's forced to admit out loud that she finds him ridiculously cute. They ultimately part on hostile terms, but events years later force ZoŽ to adopt the "Kaka"note English doesn't seem to be Greasenherr's first language, and he sees nothing funny in calling her that persona again to make a deal with Greasenherr; and even though they end up parting on hostile terms again, she's still affected by his cuteness again, and he's smitten by her coming across as a Chessmaster and Magnificent Bastard (and as controlling Bun-bun).
"My heart is filled with Kaka."
The page image is from Hark! A Vagrant, in a strip about a pirate and a British naval officer who get a little too obsessed with each other.
Perry the Platypus and Dr. Doofenshmirtz of Phineas and Ferb practically embody this trope. At the very least they're the epitome of the Friendly Enemy, treating their adversity as a job more than any actual effort to harm one another. Then there's the episode where Doofenshmirtz acquires a new nemesis which is presented as him having an affair, culminating with them on a relationship talk show together. "My nema-nema, oooooh my nema-nema-nema..."