On the Japanese web, November 28th is known as the Good Knee High Socks Day, an unofficial anniversary day for over-knee socks, usually called Knee High. Since 2013, it has been an annual event among Japanese Twitter users to upload Knee-High photos, illustrations or selfies with hashtag #いいニーハイの日.

In Japan, there are many unofficial but widely-known anniversary days designated by companies, organizations, industrial groups or persons for their promoting/awareness campaigns. Many of them enacted by a simple wordplay of dates numbers, which manner comes from a Japanese language’s characteristic that Kanji characters including numbers usually have multiple pronunciations. Additionally, “wordplay” anniversary days tends to be designated in November because “11” can be read as “I(1)I(1)” which is meaning of “Good”, “Nice” or “Happy”.

3/10: “Suger Day” → 3[Sa] + 10[Tou] = Satou = Suger
3/19: “Music Day” → 3[Myū] + 1[(Z)i] + 9[Ku] = Music
5/30: “No Garbage Day” → 5[Go] + 3[Mi] = Gomi = Garbage & Zero(0)
6/9: “Rock (Music) Day” → 6[Ro] + 9[Ku] = Rock
8/7: “Nose Day” → 8[Ha] + 7[Na] = Hana = Nose
10/2: “Tofu Day” → 10[Tou] + 2[Fu] = Toufu
11/22: “Good Married Couple Day” → 1[I] + 1[I] = Ii = Good & 2[Fū] + 2[Fu] = Fūfu = Married Couple
29th of Every Month: “Meat Day” → 2[Ni] + 9[Ku] = Niku = Meat

In the same manner, Good Knee-High Socks Day is designated on November 28th since the numbers can be read as “1[I] + 1[I] + 2[Nī] + 8[Ha(i)]” which is meaning of “Good Knee-Highs.” Meanwhile, the dawn of this anniversary day hadn’t came till late 2000s because it inherited a famous moe concept Zettai Ryouiki, or a fetish for the area of bare skin in the gap between over-knee socks and a miniskirt, that was established in the otaku culture in first half of 2000s.

Of course there will be some slightly NSFW pictures in this article, please be warned.

https://twitter.com/habisan/status/538325483989917697

https://twitter.com/erimorimo/status/538028161213034496

https://twitter.com/shiinacos/status/538181726296477696

https://twitter.com/GDGD_TODAY/status/538113637856985088

https://twitter.com/machico__a/status/537995107492827137

https://twitter.com/knee_socks2/status/448918876839899136

https://twitter.com/elfinass/status/463272913659899904

https://twitter.com/oosyare_hnaga_a/status/533458850867707904

https://twitter.com/DielhennDenes/status/533443531042328576

https://twitter.com/ysenepary/status/530884851486830592

https://twitter.com/abe3694/status/527925070203596801

https://twitter.com/niji_eroga/status/519058116663472128

https://twitter.com/knee_socks2/status/448918876839899136

https://twitter.com/moete_modaero/status/509267080550428672

https://twitter.com/elfinass/status/463272913659899904

Japan Celebrates Good Knee High Socks Day 2014 haruhichan.com

If this doesn’t do you justice, you can always search Twitter for more using the hashtag #いいニーハイの日.