Good morning everyone! 
こんな暑いと海とか川に行きたくなるよね！
Today we will be looking at 2 words that is often seen together!
陰キャ & 陽キャ
Let’s look at what each of these kanji mean.
- A place the sunlight does not shine. Shade. To get cloudy. The northern part of a mountain. The south side of a river.
- A hidden place. Something that is unknown to man. To stay inside and keep a low profile.
- Light from the sun.
- The side that faces the sun. Sunlight. The South side of a mountain. The northern part of a river.
And, what is キャ?
キャ is an abbreviation for the word キャラクター. This means that 陰（いん）キャ is short for 陰キャラクター and 陽（よう）キャ is short for 陽キャラクター
I’m sure with all this information, many of you might know or have an idea on what these words mean.
If you guessed introvert/extrovert, you are correct!
As the definitions suggests, 陰キャ refers to a person that is 暗（くら）い ‘dark/downer’ which is a word used to describe a person that keeps to themselves and are not too talkative, and 陽キャ refers to a person that is 陽気 (happy/energetic), which is a word used to describe people that are very outgoing.
Origin 
Since the origin of these words are not recorded, there are several theories of where it began. One of the theories is that it was originally used on 2ch and spread to the other parts of the internet (surprise surprise). On 2ch it was originally used to describe outgoing and quiet people.
The second theory is that it started within the anime/manga subculture to describe an outgoing main character, and a not so outgoing supporting character.
The third theory is that it is an evolved version of the slang リア充（じゅう） and 非（ひ）リア充（じゅう） since they share a very similar meaning.
リア充？非リア充？
リア充 is an abbreviation for the phrase 現実（げんじつ）(リアル)の生活（せいかつ）が充実（じゅうじつ）している (To have a fulfilling life). This phrase was used a lot a few years ago to describe people living the ‘dream life’, which usually meant having a very good romantic and social life. After reading that you might think 非リア充 is simply the opposite of リア充, but that’s not entirely true. In addition to the opposite meanings of リア充, 非リア充 was also used to refer to people who were in an unhappy relationship, people in a crappy social group, or people who were not able to keep a relationship (both romantic and social). However, since having a ‘good life’ or a ‘bad life’ is subjective, some chose not to use it and those words slowly faded away.
How/when are they used? 
The usage of these words vary and can be used in many situations. Sometimes people will use it to describe themselves…
俺陰キャだからパーティーとか苦手なんだよなwww
Since I’m an introvert, I don’t really like parties lol私は陽キャだから常に友達といないと落ち着かない
I am an extrovert to I feel like I always have to be around people.
(People say if you have to claim that you are a 陽キャ you are in fact a 陰キャ since a true 陽キャ would not care)
Examples with furigana
俺（おれ）陰（いん）キャだからパーティーとか苦手（にがて）なんだよなwww
Since I’m an introvert, I don’t really like parties lol私（わたし）は陽（よう）キャだから常（つね）に友達（ともだち）といないと落（お）ち着（つ）かない
I am an extrovert to I feel like I always have to be around people.
(People say if you have to claim that you are a 陽キャ you are in fact a 陰キャ since a true 陽キャ would not care)
And sometimes they are used as an insult.
黙っとけ陰キャ!
Shut up introvert!これだから陽キャの集まりは嫌いなんだよ
This is why I hate it when there is a group of extroverts.
Examples with furigana
黙（だま）っとけ陰（いん）キャ!
Shut up introvert!これだから陽（よう）キャの集（あつ）まりは嫌（きら）いなんだよ
This is why I hate it when there is a group of extroverts.
Although they could both be used as insults, you would probably hear/see 陰キャ used as an insult far more than 陽キャ. The reason for this is because being an introvert has a negative connotation and this is due to the culture in Japan. In Japan, people are constantly told that they must always be 明（あか）るい (cheerful) especially around people. If you aren’t 明るい you are considered to be 暗い (a downer). Since this expectation is hammered down into people from a young age, being introverted is seen as something bad by the majority, and people labeled as 暗い could be seen as the ‘creepy’ type even if they are just quiet.
陽キャ is usually used in a positive light since these people are usually very liked, always happy, and very confident, due to being 明るい. This means that the word 陽キャ is usually used in like how ‘Chad’, ‘Stacy’, or ‘Alpha’ is used in the western side of the internet. Although it is rare, 陽キャ could be used as an insult. As seen in the last example, when it is used as an insult, it is used to call someone and idiot or stupid. Why is this? This is because there is a stereotype that 陽キャ are ‘party people’ that have nothing on their mind.
チーズ牛丼 
No, I’m not abruptly changing the topic to talk about 牛丼（ぎゅうどん）.
In 2018, a picture from 2008 was posted on a thread in なんj, a 2ch board.
This is a drawing of a person ordering an extra large gyudon with three kinds of cheese sprinkled on top with a side of onsen tamago. This was actually drawn by a person called いびりょ back in 2008, when he was still in high-school. He based this drawing on himself and posted it on his blog, then 10 years later it resurfaced on a thread called 「なんJ 昼のニート無職部 part3」.
When this picture was posted, people on the board lost their minds since the person in the drawing looks like a stereotypical 陰キャ/ヲタク. From this day on, people on the internet started to use チー牛 as an insult for people that looked like they are a 陰キャ.
When 陰キャ is used it is usually used to describe someone’s personality trait. However, チー牛 is used to describe someone’s appearance along with their personality since チー牛 is short for チーズ牛丼（ぎゅうどん）を注文（ちゅうもん）してそうな顔（かお） (A person that looks like they order cheese gyudon). Due to the picture this word originated from and the nuance, it is never used in a positive way and it is only used as an insult or for self-deprecating jokes.
Lets see how this one is used.
チー牛が高級ブランドの服を着ても全然かっこよく見えない。
チー牛 do not look good even if they wear luxury brand clothes.チー牛がカッコつけんな！
Yo, チー牛, stop trying to look cool!チー牛ですみません
Sorry for being such an introvert.俺がチー牛すぎて辛い
I’m too much of an introvert that life is hard.
Examples with furigana
チー牛（ぎゅう）が高級（こうきゅう）ブランドの服（ふく）を着（き）ても全然（ぜんぜん）かっこよく見（み）えない。
チー牛 do not look good even if they wear luxury brand clothes.チー牛（ぎゅう）がカッコつけんな！
Yo, チー牛, stop trying to look cool!チー牛（ぎゅう）ですみません
Sorry for being such an introvert.俺（おれ）がチー牛（ぎゅう）すぎて辛い
I’m too much of an introvert that life is hard.
Due to the negative nuance this word has, you need to be careful when using it. For example, in 2020, the company director of SEGA said that some of the players that participated in a tournament for the game ぷよぷよ looked like they eat チーズ牛丼, which lead to a 炎上. This was most likely said as a joke, but due to the background of this meme, it could sound very insulting.
皆んなは陰キャと陽キャどっちかな？
俺は仕事しなキャ。
Fuga
If you missed the previous posts, you can check them out here!
