I think I should have introduced this when I made a post on ヤンデレ[yandere]. Well, if you have watched the famous yandere anime which origins from its doujin comics, Higurashi no naku koro ni[ひぐらしのなく頃に], you would be sure of this. L stands for Level, so L5 means level 5. And 発症[hasshou] means to sicken for illness or to develop the symptom. But what kind of level? Why 5? Yes, this stems from 雛見沢症候群[Hinamisawa Shoukougun], which means Hinamisawa syndrome. Trying not to give away any spoilers, I shall briefly explain this. This story follows a transfered schoolboy named Keiichi Maebara who starts a new life in the small village, 雛見沢[Hinamisawa]. He makes friends with several bishoujos at school, but it seems that they are hiding something horrible behind. As he tries to figure it out, he experiences a nightmare that those bishoujos become murderous.
The main reason why they become so murderous shouldn’t be mentioned here, so I must say sorry about this, but you should watch it if you haven’t. At any rate, the important thing is the level shows a person’s anger and ranges minus 5[-5] up to plus 5[+5]. When the level comes to 5, it sickens for Hinamisawa shoukougun, and drives him/her crazy. Needless to say, the action is to insult, or even to murder. That is L5発症[L5 hasshou].
Among non-otaku people, there is a similar word, マジギレ[majigire] which is an abbreviation of マジでブチギレ[maji de buchigire] which means to seriously get mad. This is a bit old, but MK5[five seconds prior to breakdown] used to be popular among schoolgirls. So when otaku people use L5発症, it means almost the same thing. Not to become like Rena. (;^^)
Well, if level 5 is the point of breakdown, what kind of symptom can be seen as of level 3 or 4? Let’s see an example with Kotonoha Katsura in School Days. While Makoto tries to ignore her, she starts to be sick in love. I think it’s level 2 when she is making a scarf for him, and it’s 3 when she is talking to the answering machine as if she is speaking to Makoto. It’s 4 when she is waiting for him under the mistletoe, and it’s finally 5 when she finds Makoto’s…So it sickens for L5発症, and she calls Sekai in order to…
However, L5発症 is not just an otaku thing anymore because this kind of thing really happens in Japan. A while ago, a 15-year-old girl killed her father while he was sleeping. She was not acting weird at all till the incident, but she had a nightmare that her father killed all of the family. So she decided to kill all of a sudden. Actually the police found out she poccessed some comics of Higurashi, so first it seemed that she became yandere all of a sudden like those girls in Higurashi. But the truth is that she had been suffered from the stress for long. Though she was an A student, her grade became worse, and got scold by her parents. Such annoyed and tired her, so she decided to end everything by killing all of the family. Yes, it sickened for L5発症. Since the father was phisically strong, she killed him first while he was sleeping. She meant to kill her mother, younger brother, and…herself.
Yes, life is hard, life is in pain. But to kill somebody changes nothing, but ruins your life. Surpassing the hardships, you can be grown-up. Don’t let L5発症 happen! But in 2D, it’s okay.