The word "seinen" literally translates to "youth" in Japanese, and, in anime/manga culture, refers to a genre of media that is directed towards male young adults in the age group of 20-30 years old—which in no way means that people of other age groups can't enjoy it, either. The word is commonly associated and sometimes confused with another genre, "shounen," and the two genres share similar attributes and features, although they have their differences, as well. Shounen is aimed at a younger audience than seinen, namely young male teenagers, and tends to have more action-fueled sequences, while seinen contains more drama elements than the typical shounen.

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Out of the hundreds and thousands of seinen anime out there, many have made their place in anime culture, but, in terms of fame and relevance, not all of them will stand the test of time. This list takes a look at some anime which might, and some that probably won't. Of course, it goes without saying that this list isn't exhaustive.

10 Will Be Around: Parasyte (2014)

Although the only similarity the anime has with Bong Joon-ho's Oscar-winning film is in its name, that isn't to say that it's any less of a masterpiece. Based on a manga series of the same name from 1988, Parasyte was produced by Madhouse Studio for many of their iconic works such as One Punch Man and Death Note. It tells the story of high-schooler Shinichi Izumi as he fuses with an extra-terrestrial parasitic organism. As the "parasyte" fails to completely take over his body, the two are forced to co-exist together as half-man half-monster and fight against others of the same kind for survival.

9 Will Disappear: Chobits (2002)

Chi in Chobits Anime

2002's Chobits was an immensely iconic and famous anime of its time, created by the highly acclaimed all-female mangaka group Clamp. Featuring gorgeous and animation and writing, the plot revolved around Hideki Motosuwa and his bond with an android Chi as they ascend the logic of conventional romantic relationships.

As the series progresses, many profound psychological themes are explored, such as the effect of advanced technology on everyday life, through the account of the personal experience of the characters. But, as undeniably good the anime maybe, it's popularity hasn't really held up in recent years, and its fanbase only shrinks in volume as time passes.

8 Will Be Around: Elfen Lied (2004)

elfen lied lucy holding a music box

Featuring one of the most hauntingly beautiful opening songs of all time, Elfen Lied redefined the definition of violence and gore in anime when it released back in 2004. But, if one were to look past all the blood and graphical violence and nudity, an extremely well-thought-out and multi-layered plot is revealed which tells the story of a group of girls who are faced with extreme abuse due to the powers they were born with but are ultimately able to achieve salvation due to the humane relationships they form.

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Although many will brush it off for being an "edgy" and unnecessarily violent anime, the anime is an indisputable classic.

7 Will Disappear: Brynhildr in the Darkness (2014)

Ironically enough, Brynhildr in the Darkness was written by the same author as Elfen Lied, mangaka Lynn Okamoto, but it doesn't reach anywhere near the heights of the 2004 classic. It's difficult not to compare the two, as they share story and character elements to a point where the 2014 anime almost seems like a rip-off of the former one.

While it attempts to deal with the same combination of violence and darker psychological themes, the blatant fan service and misplaced comedy were criticized by many to destroy the tone that the show was trying to maintain.

6 Will Be Around: Plastic Memories (2015)

Plastic Memories will be remembered by all who have seen it for a long time simply because of how horrifyingly depressing and melancholy it gets towards the end. While most anime series are based on pre-existing manga, Plastic Memories was an original anime written and produced by the studio Doga Kobo, who are known for many of their slice-of-life comedy series like Monthly Girls' Nozaki-kun and Sing "Yesterday" for Me. 

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Featuring some gorgeous animation and artwork, the story takes place in the future where people have started living alongside near human-like androids, and the focus of the story is Tsukasa Mizugaki and his relationship with an android named Isla.

5 Will Disappear: Btooom! (2012)

btooom main characters

"Typical teenage guy gets mixed up in a battle royale against his will and has to fight for his life" is not an overused concept, but one that has been tackled by many anime shows in the past such as the Future Diary series, and, specifically, in this case, it's what Btooom! is all about in a nutshell.

It has a decent enough plot featuring lots of action and adventure with a side of romantic drama, but Btooom! happens to be one of those anime that needs to keep releasing new seasons in order to remain relevant and popular. Unfortunately, the chances of a newer season are very slim at this point.

4 Will Be Around: No Game No Life (2014)

This isekai anime with animation and artwork so bright and striking to the point where it could be called "eye-straining" tells the story of elite gamer siblings Sora and Shiro who are transported to a world where every functioning part of society is decided upon by playing games. Receiving praise for its clever writing and characters—with some harsh criticism made towards its use of fan service—the anime continues to be popular even after six years.

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But fans have been yearning for a second season for a long time now, and, unless the producers are able to comply, its popularity will find it difficult to survive after the next decade or so.

3 Will Disappear: Durarara!! (2010)

Durarara!! is one of those unfortunate anime that never received the mainstream popularity it deserved despite being well-written enough to be acclaimed by a Forbes author as one of the best of the decade. This is partly due to the peculiar and haphazard storytelling style of the show.

Instead of following a linear narrative and a compact well-established cast like the majority of shows out there, set in the strange and eccentric city of Ikebukuro, it explores a multitude of storylines taking place city-wide that are connected with each other in the unlikeliest of ways; each episode focuses on a different character and retells the same incident for a different perspective.

2 Will Be Around: Tokyo Ghoul (2014)

Tokyo Ghoul Anime

Although the manga of Tokyo Ghoul is agreed upon by most to be of the seinen category, the anime tends to shift in tone between seinen and shounen from season to season. The debate about whether the anime can be considered seinen is for another time, but what everybody will agree upon is the immense popularity of the series and the fact that it's definitely here to stay.

Set in an alternate dark fantasy reality where supernatural creatures called ghouls live amongst humans and terrorize them, the anime's premise circles around Ken Kaneki as he tries to survive as a half-monster half-human after a freak incident turns him into a half-ghoul.

1 Will Disappear: Steins Gate (2011)

Regarded as one of the most well-written anime out there, Steins Gate holds a very respectable reputation in the community, at least among who have actually seen it. But, for every person who has made it to the end of the series, there are a dozen who have stopped watching it midway due to boredom and confusion.

Fans will agree that the ending is worth the wait, but the hurdle is that, in this day and age people, are less likely to wait that long for something when just shifting to a different show is much easier to do. It will no doubt remain as one of the most iconic sci-fi anime of all time, but its popularity is definitely dwindling with time.

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