Why Isn't It Attacking?

Alice and Bob have been split up against their will by the horde of flesh eating Exclusively Evil ubiquitous mooks. Alice has managed to hide, until she notices that an orc has been watching her the whole time... and hasn't attacked or revealed her location. "Why Isn't It Attacking me?", she wonders.

There are a few possible reasons, and not all are good. On the positive end, he may be a rebel good guy, or the bad guys are really Dark Is Not Evil, or their motives for chasing them were benign but misinterpreted. Or maybe this was the orc she saved years ago repaying the favor, he was once a human and feels pity, or he's lonely and wants a companion. He will usually demonstrate his good intentions by protecting Alice from other threats, which may involve knocking her out and/or taking her to his home. When she wakes up she may think she's Exploring the Evil Lair, and before long she'll be asking "Aren't You Going to Ravish Me?" followed by his puzzled "No." By the time Bob shows up, she'll likely have to stop them both from a fight over her. If the author wants to be cruel, Bob will kill him before Alice can explain.

More dangerously, he may be a Boss in Mook Clothing feigning the above as part of a dastardly plot to earn her trust so he can betray her later. Even if he genuinely does want to protect her, he can always go psychotically possessive and only protect her to possess her. Or of course, there might be a bigger monster behind her. Or just waiting for reinforcements.

Though the Example As Thesis above has an Orc, the "attacker" can be human, animal or monster.

Sister Trope to Aren't You Going to Ravish Me?. Contrast Get It Over With, Would Not Shoot a Good Guy. See also Zombie Advocate.

Anime and Manga

 * This is first played straight, but ultimately subverted in Shingeki no Kyojin, where one of the soldiers of a band of giant killers is cornered by one of the smaller giants, who desperately tries to hold back its Horror Hunger (to the point of clawing its face until drawing blood). This clues to her (and the audience) the unsettling revelation that the terrifying, humanoid giants that have plagued humanity after nearly exterminating them several hundred years ago, the seemingly unintelligent creatures who have devoured humans and caused untold atrocities for their last remaining stronghold, are not only intelligent but transformed humans. Eventually the giant succumbs to hunger and, in obvious despair, devours the unlucky scout before she can escape. This is pretty much confirmed by the protagonist and another female member who hid her condition amongst the giant killers even while squashing and maiming half the team as a giant. The former was barely able to control his descent into madness and hunger when he subdues the female member during a long fight (both in giant form).

Fan Works

 * DC Nation: During the "Strangers" plot where several Titans were swapped out with their Evil Counterparts, the thing that tipped the heroes off to something being amiss was that the people they thought were their enemies weren't attacking. Connor Hawke was the first to voice this aloud, able to read Troia's body language and quickly assess that her posture was not that of an attacker, preventing Arsenal from firing a fatal shot.

Film

 * The Host looked like it was going to do this when, but it was subverted.
 * King Kong may well be the trope codifier.
 * Happened in Alien 3. The creature gets to Ripley, who is helpless, and... hisses, and leaves. Of course, it's because.
 * Subverted in Alien vs. Predator, when the old man thinks Predator will kill him, but the Predator spares him because he is sickly. . Also The Final Girl thinks that the Predator will kill her as well.
 * Invoked in the most literal sense in How to Train Your Dragon. After Hiccup frees the Night Fury he ensnared (that is, the dragon he'd later name "Toothless"), it corners him, screams in his face, and runs off. This one event essentially kicks off the entire plot, because up until then Hiccup had been taught that dragons will always take the kill shot if given a fraction of a chance.
 * It's implied that Toothless himself has this reaction when it becomes evident that Hiccup is cutting him free rather than stabbing him.
 * The title character in Eegah!
 * The titular character of Fido is a zombie. In the film's universe, zombies are rendered docile by electrical collars, but if the collar shorts out, in theory the zombie reverts to munching on those tasty people. Through several accidents Fido's collar does malfunction, but he doesn't eat either the boy who is his "owner" or his mother. The mother actually even says, "Why aren't you attacking me?"
 * Played with in Star Wars Episode VI: "Only the fighters are attacking, I wonder what those Star Destroyers are waiting for." Not entirely straight in that the Star Destroyers weren't the threat, the thing that they thought was incapable of attacking was. The Star Destroyers were just there to box the Rebel fleet in, making them easier targets for the Death Star.
 * The climactic battle of Star Trek VI has the Enterprise under attack from an enemy ship that can stay cloaked while attacking, causing Kirk to initially order his ship to pull back. Both commanders on either side ask this question about the other: Kirk wonders why his enemy does not press his advantage; his enemy wants to make sure the Enterprise cannot ascertain his exact location before attacking the larger ship.
 * In Star Trek III: The Search For Spock, Kruge ponders why the Enterprise, which has a weapon advantage of 10 to 1, hasn't finished him off, and the captain is parleying terms of surrender instead. Kruge is Genre Savvy enough to call Kirk on his bluff.

Live-Action TV

 * In Doctor Who there are a couple of instances of Daleks not attacking despite all logic. Often justified by their weapons not working, though notably in Waters of Mars it was because.
 * In an episode of Stargate SG-1 as the team is hiding, they are spotted by Amunet as she, Apophis and a group of guards are leaving though the gate, but she does not signal their presense.
 * Occurs in Season 2 finale of Battlestar Galactica. The Caprican Resistance walks into a Centurion ambush and a bitter firefight ensues...until the Centurions just stop firing. The Resistance spend the whole night awake wondering what the frak is going on.
 * It is also an inversion: The group contains a humanoid Cylon infiltrator. When the firefight stops, he begins to wonder why his side won't attack despite numerical, technological and territorial advantages.
 * Also occurs on the Season 4 opener, where  gets into a dogfight with a Raider. The Raider gets off a scan...and breaks off. It doesn't make the poor guy happy, as he had found out moments ago that he is a Cylon and could have probably lived without the stamp of approval from a Raider.

Video Games

 * Shining Blade in Guild Wars.
 * Done by the player in Bioshock 2 if you choose to spare a certain character (who up until that point considered you a mindless monster) she'll undergo a Heel Face Turn of sorts (she won't outright betray the Big Bad, because she still believes in her and thinks she was just wrong about you, but she'll send you supplies every so often).
 * Some Splicers do the same to you. A few scripted sections have Splicers pop up right behind you and pointedly not attack. Depending on your paranoia, might count, since after you, he gives you another present and just stands there, true to his word about letting you leave..
 * Happens with in Mass Effect 2, who takes out some enemies for you, and can later potentially join your party.
 * In the comic book interquel for Left 4 Dead, The Sacrifice, a military doctor asks why the zombie horde isn't following them, but decides that it's a good thing. Louis responds that the zombies aren't attacking because a Tank is approaching, which is definitely not a good thing.
 * By the way, that scenario happens a lot in the game itself.

Web Comics

 * Eerie Cuties; when Nina and  Chloe first meet, the latter assumes the former intends to feed on her, so she nervously bears her neck while pleading with Nina to "Just leave me enough to get home tonight!" However, Nina is actually  more interested in the chocolate in Chloe's backpack.

Western Animation

 * In one episode of The Legend of Tarzan, Jane is captured by the leopard men. When she finds herself in their city, she asks why they brought her there if they weren't going to tear her apart. Turns out
 * Sometimes you wish Valerie Grey would ask this about her "Arch Enemy" Danny Phantom- who actually isn't her Arch Enemy, but actually The Hero who never attacks, but she's too blind to see it.
 * In the Avengers Earths Mightiest Heroes episode "Gamma World", Thor is fighting Absorbing Man, who has taken on the substance of Mjolnir. Absorbing Man seems to be beating Thor to a pulp, all the while shouting at the god to get up and fight. Moments later, Thor raises his hand and stops Absorbing Man in mid-swing. Thor then shows him why taking on Mjolnir's properties was a bad idea, by controlling him just like he controls his hammer.
 * Godzilla: The Series has a juvenile-sized Zilla, Jr. about to chomp on Nick Tatapolous in the first episode. What stops Zilla from eating Nick is because he had imprinted on the scientist right after hatching and thinks Nick is his "dad".