ga ryou tensei
A while ago, I read the English translation of a book called「 蛇にピアス」 ("Snakes with Piercings," or "Pierced Snakes" might have been a better title than Snakes and Earrings, which it was published as). It's about a young girl who gets involved with some guys who are into body modification and sado-masochism and possibly murder? I didn't think it was anything really special, but it looks like it's sensationalist enough to warrant a movie! You can check out the trailer at the bottom of this post.
Anyway, I mention it because the main character gets a mural tattoo on her back of a Kirin, the mythical Japanese (er... Chinese) beast most famous in the west for being a brand of beer.
I can't remember if she specifies it, or the tattoo artist advises it, but she ends up deciding not to have the Kirin's pupils drawn in. This is because of an ancient Japanese (er... Chinese) legend, which also gives us today's yoji, which means something along the lines of "Adding the eyes on the painted dragon."
1. The finishing touches.
2. The final strokes.
Look at our English equivalents. We use the painting metaphor, or the work of art metaphor to talk about finishing anything from a project at work, to an essay, to a meal, but why does the Japanese version specifically name a dragon? And honestly, if you were going to draw a dragon, or any animal-like thing, would you really draw the eyes last? Here's the legend that answers these's questions for you:
This is not the only incident in Japanese culture where the painting of the eyes garners significance though. Do you know about the still practiced tradition of painting eyes on Daruma?
梁に”張僧ヨウ”という名画家がいました。あるとき彼は、 金陵（現在の南京）の安楽寺の壁に竜を描くことを頼まれ、４匹の白い竜の図を描きました。その竜は、今にも壁を突き破って天にも昇りそうな勢いがあり、 見る人すべて息を飲みましたが、不思議なことに、瞳が描き入れられていませんでした。
不思議に思った人々が彼に理由を尋ねると、彼は、「もし瞳を入れたら、竜が天に飛んでいってしまうからだよ。」と言いました。 しかし、人々は信じることができずに、是非、瞳を描き入れるように彼に求めました。そこで仕方なく彼が４匹のうち２匹に瞳を入れると、たちまち稲妻が走って、壁が壊れ、２匹の竜は雲に乗って天に飛び去ってしまったのです。 あとには瞳を入れなかった２匹の竜だけが残ったそうです。
Somewhat perplexed, the people asked Yo for the reason he had not done so, and he answered simply "If I were to give them pupils, they'd take off into the sky and be gone." But of course, the people couldn't believe this, and demanded that he complete the mural by painting the eyes, without fail.
Having no recourse, Yo began to comply. He painted the eyes on the first dragon, and was putting the finishing touches on the second when all at once a bolt of lighting struck, shattering a portion of the wall, freeing the two completed dragons who hopped onto the nearest cloud and rode it away into the sky. After that, it seemed like a good idea after all to leave the remaining two white dragons without any eyes.
They even have Darumas that you can buy in toy vending machines, along with a sticker set to use for the eyes, like a cheaper, spiritual version of a Mister Potato Head.
Last note, but it's important to talk about the usage of 画竜点睛. While it can be used to refer to simply the fact that something is finally done (the all important Google image search reveals that it's used for things like business openings, building projects, those models of anime characters that hobbyists assemble themselves, or in mischevious references to a particular practice of omission common in manga: NSFW), it's mostly used like this:
画竜点睛を欠く, which means "lacking some final important detail without which, all the other work is useless."
Let's keep our example sentence in China as well.
I worked as hard as I could on this, but because I didn't check my translation with someone who can speak English, this translated sign is worthless due to my inability to finish it off properly.
Here's that trailer I promised you.