Checking someone's temperature by touching foreheads, usually instigated by someone completely oblivious to the intimacy.
Incidentally, this actually does work — different areas of the body have different temperatures, and if you're checking forehead-to-forehead, this provides a direct comparison (assuming the performer is at a healthy state). Of course, depending on the relationship between you and the patient, you still might want to consider using other, less personal body parts to do the checking, such as your wrist.
- Mikoto does this to Uiharu in the first chapter of A Certain Scientific Railgun. This has the Funny Background Event of infuriating Kuroko, who's in love with the former.
- Yuu does the to Ayumi in Episode 5 of Charlotte after she starts coughing to see if she has a cold or not.
- Da Capo: Junichi does this to his ill sister Nemu fairly frequently to check her temperature, and it really is a headbutt, as Nemu will infallibly complain.
- The above trope picture is from the manga adaptation of Disgaea 2, as Adell applies this to Friday, the Dimensional Gatekeeper who harbors a massive crush on him. Adell, of course, is highly oblivious to this.
- In Elfen Lied, Yuuka does this to her cousin Kohta to check if he's feverish. Unusually for this trope, Yuuka actually has a secret crush on Kohta, and although she acts nonchalant about touching foreheads together, it's clear to the audience that she's deliberately using the semi-intimate contact to try to cultivate romantic feelings for her. Kouta does this to Nyu/Lucy as well. He's completely oblivious to Nyu/Lucys reaction, apart from noting that her temperature has gone up.
- In the Girls und Panzer, in the "Motto Love Love Sakusen Desu" comic, while Miho is sick with a cold, Hana does this to her to take her temperature..
- Haruka performs one of these to Yuuto in Haruka Nogizaka's Secret Purezza. She does this in a skimpy Santa outfit, on the advice of a medical "guidebook" written by her younger sister, who's been working to get the lovebirds together the whole time. Haruka's not very aware of how shocking this is, but Yuuto is.
- Hayate the Combat Butler: Maria did this on one occasion to Hayate while he was sick. This is memorable because it is one of the few instances that Hayate takes notice of any sort of intimacy and blushes profusely. Maria however, stays completly oblivious to this.
- Hayate then performs one on Nagi, which would have been stimulating enough already, but was made worse by the fact that she had had an erotic dream about him only minutes earlier.
- Happens in Hime-chan's Ribbon, when Himeko is caught hiding in her crush's room while disguised as said crush's little sister.
- Mao uses this to check Yuriko's temperature in the Mao-chan manga. She is unaware of Yuriko's heart going all doki-doki.
- In Monster Musume Centorea demonstrates this to Suu, as Kurusu has a cold and the other girls can't enter his room without risking a lethal infection. It's Played for Laughs because not only does Suu not have the same body temperature as a human (being a semi-humanoid Slime Girl) in the first place, she's apparently unable to tell what temperature he is (or possibly even know what a temperature is, at that point in the story she hadn't even been confirmed to be sentient yet) anyway and simply repeats "42 degrees," because she heard Centorea say that was her body temperature.
- My Lovely Ghost Kana: In Chapter 7, Daikichi checks Kana's temperature by touching their foreheads together, to see if her fever's gone.
- Nagasarete Airantou: After a day of Machi actually acting like a normal girl (i.e. not pushing herself on Ikuto at every opportunity), Ikuto tells her to hold still and brings his face close. Machi goes into a Luminescent Blush in anticipation of a kiss, but Ikuto's only intention was checking her temperature because of her odd (for her) behavior.
- Negima! Magister Negi Magi:
- Negi checks Asuna's temperature with a headbutt while she is under the affects of a Love Potion.
- Chachamaru checks Negi's temperature the same way when he develops a fever near the start of the Magic World arc. In this case, however, she is the one with the crush on him. She's also nude at the time. As she is a Ridiculously Human Robot, this is apparently an accurate way for her to judge temperature.
- In No. 6, Shion checks Nezumi's temperature with a headbutt when they first meet.
- PandoraHearts: Break and Sharon give a headbutt to an ill Oz in Caucus Race as does Oz to Alice.
- Revolutionary Girl Utena: Touga does this to Nanami after she discovers the (fake) truth that they aren't actually blood related and starts acting strangely and staying in bed. It makes Nanami very flustered and she protests that she's not a kid anymore. However, unlike most examples, Touga certainly knew exactly what he was doing, and was deliberately trying to incite her feelings.
- In She's My Knight, Mogami presses her forehead against Ichinose's forehead to check if he's okay, causing him to blush.
- Happens in the Soul Eater doujinshi, Strawberry and Mint. It's done to hint at the romantic tension between Soul & Maka.
- In Strawberry Marshmallow, Nobue at one point does this to Miu, with rather icky result when Miu sneezes all over her.
- In Tokyo Mew Mew, Aoyama worries about Ichigo not feeling well, takes her to the school infirmary and checks her temperature with a headbutt.
- In an omake for Vampire Knight, Kaname does this to a sick Yuuki. She's not fazed by it; her only concern is getting him sick.
- In The Voynich Hotel, the maid Elena does this to Taizou after he awakens from a days-long fever sleep.
Taizou: Not even Adachi Mitzuru would still use that cliché. Aw, who'm I kidding...yes, he would.
- Implied in the Punch-Out!! fanfic Home Sick (NoonboryKedabory); Disco Kid notices that Aran Ryan's fever is going down while he is holding him in his arms, tussling his hair.
- A variant appears in The Dick Van Dyke Show episode "The Death of the Party", when Laura kisses Rob on the forehead at the end of the episode. When he asks if she meant the kiss as a sign of affection or as a way of taking his temperature, she answers it's both.
- Modern Family: Gloria does this to Manny. Jay, dismayed that she continues to treat Manny (well into his teens by that point) like he's three years old, says "You know we have a thermometer."
- In Undead Darlings, Pearl attempts this on Reggie in one sub event, but closes her eyes and accidentally headbutts him too hard.
- In CLANNAD, at one point you can lie to Tomoyo about being late for school by saying you were actually leaving because you feel sick. Tomoyo performs this trope, but only Tomoya is aware of the implications it would have if people saw them like this, as they are not a couple at the time.