Regardless of what temperature it is outside, lying motionless for a while has a tendency to make one feel cold. We give off less body heat when we're still, after all. So a person who's, say, falling asleep is bound to get colder more quickly than someone who's moving around and still fully awake. If that person is somehow sleeping out in the open, without a blanket (or if they've just fallen asleep in a really weird place), they may find themselves shivering in their sleep, turning over in a really fashion way, or clutching themselves. They're uncomfortable, and they show it. If they had a blanket, it has slipped off them as they've turned and shuddered.
This is, of course, a cue for another character to come along, see their distress, and react to it—by tenderly draping a blanket (or, in less providing situations, a coat) over their shoulders, petting them on the head, and saying, "Sleep tight, X." Freed from their discomfort, X usually smiles in his or her sleep, possibly clutching the hem of their new blanket for effect - even in their sleep, they're grateful for the warmth. A variant on this scenario occurs when there's only one blanket between the two characters, and Character Y must lie down beside X and share. This version is perfect for building UST.
However, the Comforting Comforter isn't always romantic. It can be used to show the affection and care between any two parties, whether they be close friends or teammates, perpetually feuding siblings, parents and children, and even old married couples. Frequently, it serves as a Pet the Dog moment for Character Y, especially if Character Y has been a Jerkass in the past to Character X -- he can be nice after all, but only if nobody's awake to know about it.
- One of Hatori's flashbacks in Fruits Basket showed him doing this to Kana, whom he'd eventually date before things went very bad with Akito.
- In the episode "Someday in the Rain" of The Melancholy Of Haruhi Suzumiya, Kyon wakes up in the clubroom with two cardigans over him. Haruhi demands hers back, but the owner of the second is up to the shippers. (Kyon makes sure the viewer knows that Mikuru did return to the room, but doesn't think about who left the second cardigan).
- In the Mai-HiME manga, Yuuichi does this to Mai. Sergei also does this in Mai-Otome.
- Early on in the anime, the usually cold and aloof Natsuki does this for Mai.
- In Episode 6 of Mai-Otome, after Arika helps Nina try to make up for her humiliating near-drowning experience by dealing with the creature that caused it, Nina drapes a blanket over her after she falls asleep writing a letter to her Anonymous Benefactor.
- In one episode of the Gravitation anime, Yuki checks in on Shuichi who's sleeping on his couch and pulls the blanket farther up to cover him more completely. Shuichi doesn't notice, but Yuki stares at him for a while after that, as if it's just sunk in that he's now sharing lodgings with another man he cares more for than he should.
- Mamori covers a sleeping Hiruma with her school jacket in one episode of the Eyeshield 21 anime (but not in the manga). He doesn't seem cold beforehand and isn't noticeably affected either, but Mamori has a reflexive maternal streak.
- In the second season of Gundam 00 Tieria does this for one of the Bridge Bunnies, though not so much as a romantic device as a demonstration of exactly how much Tieria has grown as a character from the Jerkass he was in season one.
- Seto Kaiba from Yu-Gi-Oh! once used his longcoat to tuck in Mokuba, who had fallen asleep in a chair.
- An early scene in Magical Girl Lyrical Nanoha A's that showed Hayate's maternal bond towards the Wolkenritter had her doing this to Signum and Zafira after they had fallen asleep in the living room.
- Seen in one chapter of Vampire Knight Kaname Kuran comes back to the Moon Dorms and sees Yuki sleeping on the stairs after she waited for his appearance. He covers her with his coat.
- Negi of Mahou Sensei Negima is shown doing this to his students after they exhausted themselves giving Chao an all-night Goodbye Party during the Mahora Festival arc.
- In Fullmetal Alchemist, Winry does this for Ed; but it's totally platonic.
- Yeaaaaah that's what he tells himself.
- Riza Hawkeye wraps her jacket around Ed at one point. He's awake, but it's been raining and he lost his coat in a recent fight.
- A brief scene in Digimon Tamers has Takato drape his sweatshirt over a sleeping Guilmon.
- In Princess Mononoke, Ashitaka does it to San. Then San does it to Ashitaka.
- In Spirited Away, Kumaji manages to show that he's not so grumpy after all by draping a blanket (well, cushion) over Chihiro after she falls asleep on the boiler room floor.
- Used a couple of times in Gun X Sword. Van gives one of the early hints of his Hidden Heart of Gold by covering Wendy with his coat after she faints (all we see is her waking up to discover the coat). Later in the series, Ray demonstrates that he still cares about his brother by covering him with a blanket while he naps.
- Used in Full Moon wo Sagashite anime when Takuto finds Mitsuki asleep at her desk. He shows his his heart of gold by covering her with a blanket and smiling warmly. Though later when she inquires about it and thanks him, he blushes and decides to change the subject . In another episode, he covers her up with his parka while she's sleeping inside a lighthouse.
- Gunslinger Girl. On seeing cyborg girl Triela lying on a bed clutching one of her teddy bears, her handler Hilshire pulls the blanket over her.
- In Daily Lives of High School Boys Hidenori does this for Literature Girl, after he manages to knock her out as an end of her unlucky combo.
- DC example, featuring a cape instead of a blanket. In Young Justice: Sins of Youth, the Justice League of America and Justice Society of America have been turned into kids, while the members of Young Justice and other young heroes have been aged. One of these heroes is Star-Spangled Kid (Courtney Whitmore, now Stargirl), who becomes Starwoman thanks to the age reversal. As the JSA goes to an alien planet to pick up some phlebotinum, she gets into an argument with another hero on the trip, Merry the Gimmick-Girl, who was the adopted sister of the original Star-Spangled Kid. She really doesn't like Courtney because she's "dishonoring" SSK1's legacy. (Merry does have a point: Courtney stole his equipment.) Anyway, during the adventure, Courtney proves herself, and she and the JSA Junior take a nap. While she's sleeping, Merry covers Courtney with her cape. Definitely an aww-inspiring moment.
- There's a scene in the Elf Quest: Forevergreen arc (by the notorious Barry Blair) where the villain Door sees one of his scantily-clad slave boys sleeping on the floor and puts a cloak over him. Definitely a capricious gesture since Door has killed other slaves on a whim.
- Played with in the Kim Possible fic "Maslow", in a scene where Shego throws a blanket over Drakken (who had fallen asleep while working on one of his projects), then immediately removes it because she couldn't stand him knowing she'd done it. She goes back and forth several times before giving up and leaving the blanket draped over him.
- A non-sexual one in Destiny's Pawn Kairi (Revan) has trouble sleeping and checks in on Mission. While she's adjusting the blanket, Carth catches her. This leads to a conversation about What Is This Thing You Call Love? where they both admit that they love the girl "as if she were [their] own."
- A fanart has Batman covering a sleeping Robin with his cape.
- Skinner does this for Elizabeth twice in The Private Diary of Elizabeth Quatermain. She dozes off in the Amazon rainforest, and again in the library of the Nautilus. The first time he covers her with his coat; the second time he carries her to her own bed.
- In The Emperors New Groove, Pacha covers a shivering Kuzco (in llama form) with his coat even though Kuzco has been nothing but a Jerkass to him so far. This gesture of kindness marks the first step up in relations between Pacha and Kuzco.
- In Snake in the Eagle's Shadow the Old Man does this for Chien, who is the whipping boy for the martial arts school where he's been raised.
- Used as an intentionally cliched romantic device in Spaceballs. Lone Starr gives Princess Vespa his jacket in the middle of the freezing desert.
- Rachel covers Heck with a blanket after he apparently falls asleep on the couch in Imagine Me and You. However, he later pushes it off, revealing that he'd been pretending to sleep and had heard her confession of infidelity.
- Both main stars of Look Who's Talking (baby excepted) do this to each other.
- Earl uses this trope to play matchmaker with Valentine and Rhonda in Tremors.
- In The Incredible Hulk, Betty puts her jacket on the sleeping Bruce Banner.
- Played straight in Treasure Planet, when Long John Silver places his coat on a sleeping Jim Hawkins.
- Skeevy example in Fish Tank, when the sleeping fifteen-year-old Mia is carried to bed by her mother's boyfriend, who proceeds to take off her shoes and trousers before tucking her in. This could easily be interpreted as a fatherly rather than inappropriately sexual act, until later events make it clear how he sees her.
- A sweet scene between Mr Han and Dre in the remake of The Karate Kid, where Mr Han lets a sleeping Dre sleep on his lap and even hesitatingly place a hand on his shoulder.
- A particularly funny example from "Wet Hot American Summer" in which Coop sees Katie shivering, so he gives her his flannel. Then Coop is chilly without his flannel, so Katie gives him her sweater. Katie remarks how nice Coop's flannel is, which reminds him how much he likes it.
Coop: That's actually my favorite shirt.
Coop: So you're going to have to give it back. Now.
- Twice in the 1927 film Sunrise. Near the beginning, the Wife covers the Man with a blanket after he comes in late, even though she knows he's been out philandering. Then, near the end, the Man shields his wife from the wind with his coat as she dozes on the boat.
- In The Blues Brothers, Elwood does this to Jake.
- In Lord of the Rings (The Return of the King), Aragorn adjusts Eowyn's covers shortly before she wakes up from a nightmare.
- At the end of West Side Story, after Tony's murder, Baby John covers Maria's head and shoulders with her scarf - one of the first gestures of friendship shown by one of the Jets towards one of the Sharks.
- Done in Lois McMaster Bujold's Shards of Honor, as a hint that our heroine isn't as revolted by the hero as much as she likes to think she is.
- In Master and Commander, Marshall drapes a blanket over a sleeping Jack.
- Monsieur Paul does this for Lucy Snowe in Villette
- In Winnie the Pooh'sGrandAdventure, Rabbit gives half of the torn map he's using as a blanket to Pooh.
- The patient in Beachwalker does this for the person who’s trying to save his life. Since there is only one blanket, it takes him several tries to convince her to actually use it.
- In a complicated example, Cartwright does this for Adrian in The Liar Novel. Except Adrian's only pretending to be asleep, and he's not so happy about it since he was hoping for something else entirely.
- Friends, in "The One with the Ick Factor", Rachel sleeping on the couch, Ross with the blanket.
- Dawson's Creek. There's an instance of Dawson placing a blanket over a sleeping Mr. Brooks, whoever that is, but surely it must have happened with the members of the love triangle as well.
- Happened in Black Books, with Bernard tucking in Fran.
- In Ashes to Ashes, Alex has drunk too much (again) and has passed out on her couch. Gene, also tipsy, covers her with a convenient blanket and staggers off, back to work. Considering how much time the two of them spend fighting, it's a very sweet moment.
- The page image is from the Doctor Who serial The War Games. The hands belong to Jamie, draping the coat over Zoë.
- Tin Man: The DG/C shippers certainly noticed the fact that when DG woke up from one of her crazy dreams, Cain's Badass Longcoat had been pressed into service as a blanket.
- In non-sexual examples (honestly!), most of the characters from M*A*S*H drape blankets over someone exhausted in what are always very sweet moments; Radar has done it for Hawkeye and Trapper, Henry and later Potter have both done it for Radar, Hawkeye has done it for BJ and BJ has done it for Hawkeye.
- Divya slips a coat over a sleeping Evan when he falls asleep waiting for news on his father. Given her normal perpetual state of annoyance at him, it's really sweet.
- A variation of this happens in Merlin: a spell has put everyone in Camelot to sleep, and when Merlin and Arthur return to the kingdom they find everyone passed out wherever they happened to be when the spell hit. Arthur gently picks Guinevere up from the floor and puts her on a bed. (Everyone else is left on the ground).
- In the NCIS episode "Twilight", Gibbs covers Kate with her own jacket while she is sleeping behind her desk in the office. Maybe not crowning, but it is a heartwarming moment. Considering how the episode ended, also a Tear Jerker in retrospect. Many seasons later, this returns in a flashback as Gibbs does the same for Dr. Rachel Cranston, Kate's older sister.
- At the end of The X-Files episode 'All Things', Scully falls asleep on the couch while talking to Mulder. He pauses to brush a lock of hair from her face and gaze at her before covering her with a blanket. It's pretty adorable.
- This is also very much a romantic example, since it's heavily implied they slept together for the first time later that night.
- In a later episode of 7th Heaven, Kevin covers his soon-to-be-wife Lucy with a blanket when she conks out while studying.
- In what may be considered a clever variation of this, the Star Trek: Deep Space Nine episode "The Muse" has Odo, a shapeshifter, literally turning part of his body into a blanket and wrapping it around Lwaxana Troi, who is sleeping on his lap.
- On Boy Meets World, Mr. Turner does this for a then-homeless Shawn when he falls asleep on his couch. It's one of Mr. Turner's first steps towards becoming a substitute father-figure for Shawn.
- Watson to Sherlock Holmes after his friend falls asleep on his consulting-room table in the Granada TV version of "The Empty House".
- Sharpe is camping in the woods with Theresa and her partisans. He sees her shiver in her sleep and so quietly drapes his uniform coat over her. She doesn't wake, but smiles and snuggles down into it.
- Kung Hyuk in Flower Boy Ramyun Shop wakes up late at night and checks to see if Eun Bi is home, he covers her with the quilt she knocked off and takes her glasses off when she went to sleep with them on.
- At the end of Journey's End Stanhope tucks in Raleigh and ruffles his hair after Raleigh is hit by a shell, paralysed and probably has minutes to live.
- Tales of Phantasia, the first of two romantic scenes. There Is Only One Bed, so Cless and Mint look embarrassed at each other for a couple of seconds, and then Cless mumbles, "I-I'll sleep on the floor..." and practically runs away. A moment later, he's fast asleep, and Mint brings him a blanket and pillow.
- At the end of the Painted Black arc in El Goonish Shive, Mr. Verres does this to both Tedd and Grace.
- Banquo of Goodbye Chains covers a sleeping Colin with his coat after Colin takes a bullet for him (and after, of course, Banquo has treated said wound). Colin then tries to snuggle up against him.
Colin: looove you
Banquo: [pushes him away] No way, no how.
- OC!Scotland from Axis Powers Hetalia, despite what other fanworks had portrayed him as, was quite gentle with a sleeping England. When no one was around that is.
- When the Devil goes on vacation, Lil' Evil holds a candlelight vigil and falls asleep by his booth. Seymour brings him a blanket.
- In one episode of Rugrats, Tommy and Chuckie, normally the best of friends, get into a fight when Tommy stays over at Chuckie's house for the night. They fight over the blanket in their crib. Tommy wins, but Chuckie shivers in the cold. So Tommy gives in and shares the blanket with him.
- The Simpsons had Bart give Lisa a blanket when they were stranded in the woods. Said blanket was the flag Lisa made and Bart ruined. A bit of a subversion as Lisa was still awake.
- The Brave Little Toaster
- Oddly enough, the scene involves a character that IS a blanket.
- In the Phineas and Ferb episode "My Fair Goalie", Perry the Platypus does this for an ill Dr. Doofenshmirtz, with a blanket pulled out of his fedora.