I'm surprised, that no one suggested Ai-Ren. I think you should definitely try it, if you are not bothered by some nude scenes.

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"Thus is our treaty written, thus is agreement made
Thought is the arrow of time, memory never fades
What was asked is given, the price is paid"

^ omg I've completely forgotten that manga. I second that.

Saikano - painful
Fire Candy - twisted
Kurozuka - twisted

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Dunno if someone has already recommended this but Oujitachi wa Izonsuru

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Recommend me horror , yaoi and shoujo manga please

I came here to say this -- hellishly twisted.

And I second Saikano, painful indeed.

You might like:
Rec - Kimi ga Naita Hi - http://www.mangaupdates.com/series.html?id=58616
The Snow Queen - http://www.mangaupdates.com/series.html?id=23824
Camelot Garden - http://www.mangaupdates.com/series.html?id=31647
Kanojo ga Tonda hi - http://www.mangaupdates.com/series.html?id=16261
Deep Love - Ayu no Monogatari (& any other story in this series) - http://www.mangaupdates.com/series.html?id=1121
majo to yajuu - http://www.mangaupdates.com/series.html?id=72796
Kagerou Inazuma Mizu no Tsuki (and others by mangaka) - http://www.mangaupdates.com/series.html?id=6321
First Love - Anata ga Watashi o Sabishiku Saseru - http://www.mangaupdates.com/series.html?id=22382
World End Garden - http://www.mangaupdates.com/series.html?id=64991
Ningyou Saisei Koujou - http://www.mangaupdates.com/series.html?id=71030


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Remembrance, a forsaken thing that revokes ignorance and leaves people in doubt, is my only redemption and solace deep within the cascade of white.
* * * * * * * * * * * * * * * * * * * * *
The evergreen trees speak of days long past when music mingled with the wind and sweet murmurs brushed our cheeks.

I think six half would work well. A brother sister relationship, and memory loss. It's an engaging read with a strong female lead to boot. It's quite serious with some grating scenes.

If you don't mind light novel : Utsuro no Hako to Zero no Maria (Novel)

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Just FYI, but OP of this thread first posted a year and half ago and OP's last forum activity was more than a year ago.

Thanks for your concern. Just FYI, this post are open for anyone who looking for similar thing with the OP.

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Fukashigi Philia has a lot of twisted bits if you stick with it, but is more focused on mystery/action.

I'm sure someone already posted Aku no hana, but I'll put it there.

Koru no hibi has some ecchi bits and is kinda light hearted compared to everything else, but for the most part is solid.

Basara ?