Headbutt Thermometer

You aren't helping, Adell...

Checking someone's temperature by touching foreheads, usually instigated by someone completely oblivious to the intimacy.

Very often ends up a case of I Didn't Mean to Turn You On. See also Headbutt of Love.

Incidentally, this actually does work, and it even works better than using other body parts. Different areas of the body have different temperatures, and if you're checking the 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.

Not related to mixing up rectal and oral temperature measurement devices.

Examples of Headbutt Thermometer include:

Anime and Manga

• Misaka 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 her.
• 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.
• Da Capo: Junichi does this to his Ill Girl sister Nemu fairly frequently to check her temperature, and it really is a headbutt, as Nemu will infallibly complain.
• Mahou Sensei Negima: Negi does this to Asuna 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.
• Naruto: The Mizukage and her teenage bodyguard, Chojuro.
• Haruka performs one of these to Yuuto in Nogizaka Haruka no Himitsu 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.
• In To LOVE-Ru, Lala does this given any excuse, invariably wearing a Naughty Nurse Outfit.
  • Rito does this to Mikan in Darkness while Celine's flower is on her head.
• Maria did this on one occasion to Hayate (along with removing his shirt) 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.
• Masaya to Ichigo in Tokyo Mew Mew.
• Samatarou does this to Tenko in Kamisama Kazoku, not knowing about her crush on him.
• Happens in the Soul Eater doujinshi, Strawberry and Mint. It's done to hint at the romantic tension between Soul & Maka.
• 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 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.
  • At least in the manga, 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.
• Aoi to Kaoru in Ai Yori Aoshi. He freaks for a second because it looks like she was coming in for a kiss.
• In Ichigo Mashimaro, Nobue at one point does this to Miu, with rather icky result when Miu sneezes all over her.
• 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.
• Shion to Nezumi in No. 6. Of course if the preview already has people wondering...
• The above trope picture is from the manga adaptation of Disgaea 2: Cursed Memories, as Adell applies this to Friday, the Dimensional Gatekeeper who harbors a massive crush on him. Adell, of course, is highly oblivious to this.
• Happens in Hime-chan no Ribon, when Himeko is caught hiding in her crush's room while disguised as said crush's little sister.

Live Action TV

• House once does this to Wilson.

Visual Novels

• 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.