are there any manga with main character that has a sad/tragic past?

Sorry in advance for the long answer :)

1) +ANIMA

Link: http://mangafox.me/manga/anima/

Details: Everyone has a sad past, but the girl Nana and the boy Husky (mostly him) have especially tragic ones and everyone's really surprised when the truth comes out. It may not be your thing, but it's still a good read and has some funny bits too. And Husky is really cold/a bit mean to others because of his past but he's actually a softie. It's a really sweet manga with some shocking bits in there. Forgot to add this (edited in) but the main theme is friendship so there's very little romance.

2) Deep Love - Ayu no Monogatari

Link: http://mangafox.me/manga/deep_love_ayu_no_monogata...

Details: Both the boy and the girl in this have very tragic backgrounds. It's really sad but sweet at the same time.

3) Annarasumanara

Link: http://mangafox.me/manga/annarasumanara/

Details: This manhwa takes a while to get into but it's simply amazing. The art is fantastic and the three main characters have tragic pasts. Just to note, I know one of the main characters is drawn with a long face (you'll know what I mean when you see him) but I promise you you'll see the reason why towards the end. It's just amazing.

4) Gantz

Link: http://mangafox.me/manga/gantz/

Details: Okay, this manga is includes gore and fighting, but it's very very very good. The main characters all meet in this 'limbo land' where they go to once they die, so of course there are going to be some sad reasons why people have died. It's not as tragic as the other manga's, but it's worth a shot.

5) 3 Level Combination

Link: http://mangafox.me/manga/3_level_combination/

Details: I've read this three times so far this week and every time I've finished crying. My god it is so sad. it's by the same person who did Annarasumanara and it has the same sort of feel like that. 3 level Combination is all coloured as well and it's just so beautiful - it takes a while to get into but as soon as the robot gets introduced then it goes along quite fast. Very enjoyable!

6) GOGGLE

Link: http://mangafox.me/manga/goggle/

Details: I put this in here for a bit of variety, it's very short (a one-shot) about a young girl who can't takes there goggles/glasses off because of something bad happening to her. It's a really uplifting manga and really cute.

7) Confidential Confessions

Link: http://mangafox.me/manga/confidential_confessions/

Details: Pretty much everyone in this has a sad/tragic backstory. The plot isn't quite as deep as the others, but it's still an enjoyable read.

8) Orange

Link: http://mangafox.me/manga/orange_takano_ichigo/

Details: I hate any lovey-dovey sort of thing but I really liked this manga, which is saying something. It hooks you in and one of the main characters has a tragic backstory. I can't really give you much more without giving away the plot.

9) Jigoku no Alice

Link: http://mangafox.me/manga/jigoku_no_alice/

Details: The art style in this is probably very different to what you're used to. But it's a really interesting/deep manga. The manga follows a young mentally unstable boy (with the tragic past) and a human/robot fetish doll (Like a sex robot, but he looks after her like a brother) as they travel across an post-apocalyptic world. There's also another manga called Becchin to Mandara with the whole sad/tragic past by the same author too.

10) Sket Dance

Link: http://mangafox.me/manga/sket_dance/

Details: This manga is unlike all the others because the main theme is comedy. It's hilarious and a brilliant read. One of the main characters (his name is Switch) has a really really really tragic past which explains his behaviour and his best friends are really shocked when they find out. But his background isn't revealed until quite a way into the manga.

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