Ear Cleaning

Also known as Mimikaki, ear cleaning is a mostly Asian practice, as generally Asian peoples' ear wax is harder and more lumpy than westerners'. It uses an ear pick (often shown with a puffy, cotton-ball like thing on the end) to remove wax from the inside of the ear. Because having this done to you by another person is considered intimate, this is usually seen in anime and manga between parents and children, siblings, or two people who are lovers. As such it can be used for variations of Does This Remind You of Anything?, Visual Innuendo and even Accidental Innuendo.

It's a pleasant experience akin to having one's back scratched, and the sight of someone cleaning out another's ears is almost always an indication of a close, warm relationship.

(Note that this method of cleaning your ears is not exactly medically approved, due to the risk of getting things stuck or potentially perforating your eardrums. Not that it stops anyone...)

Examples of Ear Cleaning include:

Anime and Manga

As shown in the image above, Kagami does this to her sister Tsukasa in Lucky Star.
- One of the character sketches in the manga shows the twins' mother Miki holding an ear pick while asking her husband to come closer.
In Ranma ½, Cologne can be seen doing this to her great-granddaughter Shampoo in an early chapter of the manga.
Similarly, in Rumiko Takahashi's earlier series Urusei Yatsura, Lum does this to Ataru on several occasions. In the anime version, specifically, the first time it happens is at the end of the second 'chapter' of episode 4. She's also seen doing it to him at school in the 17th episode.
Darker than Black features an Innocent Innuendo situation that turns out to be a widow cleaning out the ears of the private investigator she hired. Though for him it might not have been completely innocent...
The Adolescence of Utena features Shiori cleaning out Touga's ears during their sex scene.
Chie-sensei in the first episode of Sayonara Zetsubou Sensei performs this on herself in a way that's not just a bit suggestive, even commenting that it's "no wonder that people enjoy this."
Tomomi does this off for Kouichi in Moonlight Lady, much to the chagrin of Io.
Bes and Karala pull this off towards the end of Space Runaway Ideon.
Elda does the for her son in Karin. He meets the hazard, as well.
In Hidamari Sketch, when Hiro, Miyako, and Yuno walk in on Sae's room and find her asleep on the floor with a note on the progress of the story she's writing, Hiro kneels down and puts Sae's head on her lap. Yuno, charmed at Hiro and Sae's intimacy, runs over and offers Hiro an ear pick, to Hiro's confusion.
Happy Lesson gives us a terrifying version in which Chitose is Strapped to An Operating Table and ends up with a punctured eardrum.
Done by Vanilla for Kokomo in one Galaxy Angel Party manga where Kokomo thinks Vanilla is his mom.
Rather unusually done for Manji by Rin in Blade of the Immortal.
One of the (very many) outlandish schemes to conquer Earth in Keroro Gunsou involves using an energy wave that causes earpicks to appear in people's hands while giving them the subliminal urge to do this to whoever is next to them.
There was a scene in a much earlier anime, where a maker of traditional wooden earpicks is almost phased out by a newfangled invention, the Mimikaki Machine. Resembling a sewing machine with a woman's folded legs at its base and a mounted earpick over it, the horrific implications became clear as the machine was turned on, and subsequently started bucking and jabbing up and down like an unbalanced washing machine.
Occurs in Change 123 when Kosukegawa imagines Motoko as his wife.
Source of a Crowning Moment of Funny in the manga Osuteki Darling. Protagonist Seri's brother-in-law wants to clean his wife's ears. She refuses, then says with a blush "The inside of my ears... are for Seri only." He then slowly turns to Seri and declares "You're my enemy!"
In Samurai Gun, Hooker with a Heart of Gold Ohana does this for Ichimatsu, then suggestively asks if he wants anything else. Given his Celibate Hero nature, Ichimatsu doesn't.
One ending stinger panel of Case Closed has Heiji's dad submitting to an ear cleaning in which Mrs. Hattori was rougher than usual, being unhappy that he put Heiji in danger.
Seitokai Yakuindomo episode 5, but besides the Innocent Innuendo because a certain someone misheard, it's played straight. Lap, pick in ear, feels good.
Sana from Kodomo no Omocha does this at one point to Hayama when she wants to teach him what it is like to have a mother. They become a couple later on.
In a sweet subversion of Futari Ecchi's usual stance that All Men Are Perverts, when Yura offers to do "anything" for Makoto, he asks her to do this.
In the second season of Ah! My Goddess, Keiichi gets his ears cleaned by Belldandy in one episode and Hild in another.
Atsushi's fiancee does this to him in a chapter of Higanjima
Poor Poor Lips has a chapter that revolved around Nako cleaning Ren's ear. The intimate subtext of the act gets lampshaded for all its worth.

Nako: (Describing her ear cleaning technique) You gently tickle the outside of the ear before you remove the earwax. That helps the person relax, so the hole opens up wider.
Ren: (thinking to herself) ... Foreplay?

Otae does this to her future grandfather-in-law in Gintama in a show of how perfect a wife she would eventually be for the Yagyuu heir. And then she pulls out a really large blob of...stuff from the old man's ear. Horrified, and with some effort, she shoves it back in.

Film

In the Chinese epic The Emperor's Shadow (Qin Song), the emperor's adult daughter cleans his ears with a wooden pick; at one point she holds his eardrum hostage with it in order to extract a favor from him.

Literature

In the novel No Longer Human by Osamu Dazai, Takeichi got an ear infection from staying outside in the rain so his friend Yozo cleaned his ears. Takeichi commented that Yozo's kindness can get him anything he wanted.
In a scene in Japanese-Canadian author Hiromi Goto's novel Chorus Of Mushrooms, the main character's mother cleans her ears, which helps bond mother and daughter.

Video Games

In Higurashi no Naku Koro ni having to do this was a frequent penalty in the club's punishment games.
You must do this to have sex (or Hot Cocoa) with the girls in order to win their affections in Steambot Chronicles.
During Lisianthus' path in SHUFFLE!, she does this to Rin as his birthday present to her
In Miki's route in Cross Channel, she does this for Taichi. It's actually incredibly painful for Taichi as Miki basically forces him into it.