In Coming Back, Jake Long fathered a newborn named Benjamin. When Rose asked Lao Shi if Ben will become a dragon, Lao Shi said he didn't know and that they would know "when he is older". Soon after that, Ben let a "small burp" show that he has fire-breathing. Lao Shi replied that "He is a few minutes older from when I made the statement."
Mass Effect Clash Of Civilizations: Sergio Augusto said that the main armament of the Eternal Light of Sol was used on "a barren, resource-poor planet". He dind't mention that it destroyed every single Jiralhanae ship in its orbit.
In Masters of Death, after Draco insults Mandy while trying to befriend Harry, Harry declares that their friendship will last the rest of Draco's life. They kill him right after the train arrives in Hogsmeade.
In End of the Line, Sailor Moon's spell drew magic out of "everything fighting" to power a barrier that would protect her hometown from an apocalypse the Sailor Scouts had foreseen. Xander furiously berates her and Luna for this because "survival of the fittest" means everything alive is constantly fighting to survive. As a result, they ripped magic out of everything, causing the apocalypse in the first place.
In Chapter 2, Monobear stated that since Matsukaze had suffered internal bleeding, his statement that “there was no significant blood loss” was true, since most of the blood was still inside Matsukaze's body
Also in Chapter 2, the graduates use this against Monobear, stating that since Hikasa had received authorization from one of the Monobear spares, he had not broken the rule about not entering the Principal’s Office without authorization, even if the permission itself didn’t come from the real Monobear
In Hunting The Unicorn, a statement that Blaine made ("I've never been anyone's boyfriend") is played with in the most depressing manner possible: He really hasn't had a boyfriend before Kurt — he just thought he did. And it was a disaster.
In the Fates Gambit, Child Services went to the Dursley household to ask questions about their treatment of Harry Potter. Dudley told it all and, when asked if his Dad ever asked him not to tell anything, he told his Dad told him never to mention anything if it outside the house. Fortunately, Dudley didn't understand it'd be equally bad for his parents to have it mentioned to the authorities inside the house too.
Draco Malfoy gets screwed out of a couple of Sex Slaves this way in The Harem War. The Death Eaters forced the Greengrass family to make an Unbreakable Vow that their two oldest daughters would be sold as slaves to the next Lord Black, assumed to be Draco. Unfortunately, thanks to Sirius' machinations, Harry turns out to be Lord Black instead, and thus, he gets the daughters instead.
Harry: Wait... Didn't Draco order you not to try to save my life or to try and drive me from the castle? Dobby: Dobby wasn't trying to save the Great Harry Potter's life nor was he trying to send him away from Hogwarts. Dobby was trying to break Harry Potter's arm.
In The Human Doctor, the terms of Lauren's servitude with the Light are: full servitude and no contact with the outside world, in exchange for offering her the full resources of the Fae to cure Nadia of her illness, with the stipulation that she never be used to harm to kill anyone. The exact wording is used against her twice. When a Fae clan is suffering from a STD, Lauren is forbidden to treat them, as the Ash is punishing them. He justifies it by pointing out she isn't harming them, the disease is. This does not alleviate her guilt, but she has no choice. Later Lachlan reveals that the Ash knew all along that Nadia wasn't sick, but cursed and knew how to end it, and was merely exploiting her. If Lauren directly asked him about it, he would have to answer truthfully. But since she didn't ask, he didn't tell. Note that this is actually better than the canon version, where he actually ordered the curse in the first place.
Lauren later panics when she learns that Kenzi made a deal with The Morrigan, musing that she read the fine print and the Ash still screwed her; and Kenzi's deal is far too broad for them to have any chance. She then says that if Kenzi makes any other deals with the Fae, to please have her, Trick, or Dyson go over it and look out for exact wording.
In 120 Days of Blueblood, Prince Blueblood does this twice. In the first chapter, he arranges for Rarity and Sweetie Belle's father to be framed and arrested, and Prince Blueblood promises Rarity and Sweetie Belle that if they service him to his satisfaction, Blueblood will reunite them with their father. Rarity and Sweetie Belle assume that this means he'll let their father go, but actually, their father was executed a while ago. Blueblood reunites Sweetie Belle and Rarity with their father as he said he would, by executing them as well so they can be reunited in death. In the third chapter, Blueblood has Pinkie Pie arrested on a false charge of being a witch. Pinkie Pie manages to persuade Blueblood to let her go home unharmed if she does everything Blueblood wants. After Pinkie Pie provides him the services he asks for, Blueblood has his guards make sure Pinkie Pie arrives back in her gypsy wagon safe and sound, exactly as he promised he would. Then he has the guards seal the wagon's doors and windows shut and has the wagon thrown in the ocean so Pinkie Pie drowns. After all, Blueblood never made any promises about Pinkie Pie being unharmed after being escorted home.
A Brief History of Equestria: King Aurum uses this to insure that Princess Platinum takes the throne without having to marry (and give power to) any of the corrupt nobles. As he points out, Unicorn law says that Queens can't rule, but not that a mare can't be King.
In Diaries of a Madman, both Navarone and Discord love this trope. The former practically makes it an art form, given how often he does it.
Inner Demons: When Applejack is captured by Queen!Twilight's forces while trying to rescue Rarity, she promises to not try to escape. As she and Rarity are breaking out, she explains that she has no intention of trying to escape; they are going to escape.
This also pops up during the Final Battle — Queen!Twilight said that she would wait for the heroes in Tartarus to fight them one final time. However, as Scootaloo points out, she didn't say that her army would wait, and indeed her Elite Mooks start marching on Ponyville while she's fighting the Element bearers. Fortunately, the Royal Guard shows up to keep them busy.
The Nuptialverse: Chrysalis sold out the Founders of Equestria to Discord when he offered to give her the power of all three pony races, which she took to mean he'd turn her into an Alicorn. Instead, he turned her into a changeling — apparently, he found the idea of just turning her into an Alicorn too boring.
The Powers Of Harmony: Technically speaking, everything the Guards tell the Mane Six about their pasts are true. They just leave out that it all happened a thousand years ago.
Naruto: "There are two rules to making a deal with a demon. 1) Don't. 2) If you have to make a deal, be sure to read the fine print."
This fanfiction features several instances of the trope in action. In chapter 45, Naruto and Anko capture a traitor and make him watch as his cousin is killed right before his eyes. When he begs not to be killed, Naruto tells him that HE won't, provided the traitor cooperates. Anko makes no such deal. So when the traitor spills everything he knows, Naruto walks away, keeping his word, but leaving Anko, or one of her summoned snakes, rather, to finish the traitor off.
Anko: "Your cooperation has been much appreciated!" Traitor: "You're welcome." Anko: "And to show our appreciation, I won't have Uwabami-chan, here, eat you alive!" Traitor: "Thank y-" Anko: "She's still gonna eat you; you'll just be dead."
In Farewell Match, boxer Ricky Redman faces a powerful alien in a match where "the loser dies". Despite his best efforts, Ricky loses, only to be informed that, "You will die the death of obscurity, human. While your physical existence will continue, your name will be forgotten, and your former fame will fade into nothingness. You will never again throw a punch inside a ring! That, human, is your fate!" The crowd and his sleazy manager starts mocking him, but Ricky gets the last laugh by pointing out that they never said anything about throwing a punch outside of the ring, and beats the crap out of his manager.
This, so Kyubey claimed, was what doomed Joan of Arc in A History Of Magic. She had wished that France would hear God through her and free herself. And it was true, she would become an inspiration and spur France to free itself from English rule. She just had to die to do it. That knowledge was enough to turn her into the witch Elektra.
In the Star Trek: The Original Series fic Insontis II, when the admirals call to complain about Spock using the age-regression technology, Kirk reminds them that they gave the Vulcan carte blanche in his investigation.
Kaiba: I'm shutting down your research lab, Nesbitt. Nesbitt: Mister Kaiba, I beg you to reconsider! Kaiba: Kay. (shot of lab being blown to smithereens) Nesbitt: But you said you'd reconsider! Kaiba: I did. I was going to have the building renovated after I shut it down. Nesbitt: Then why did you— Kaiba:I reconsidered.
And this gem in Episode 55…
Kaiba: Oh hey, that reminds me of a joke. Why did the obnoxious green-haired punk cross the road? Noah: What? Kaiba: To show that he had guts. And man, did he have guts. Noah: That's not funny. Kaiba: I guess you had to be there. Noah I WAS. Kaiba: And that's why it's so funny.