I can't choose just one manga as a must read because there are so many that I love. I guess it all depends on your preferrence, but maybe one of these will catch your eye if they haven't all ready.

1. After School Nightmare:
A shōjo fantasy manga by Setona Mizushiro. It was serialized from 2004 to 2007 in the manga magazine Princess and collected in ten tankōbon volumes. It is licensed in North America by Go! Comi, with all volumes published. It is about Mashiro Ichijo, an intersexed high-school student who is made by a teacher to work out his gender identity in a collective dream, and Mashiro's romantic relationships with two classmates, one female and one male.

2. Juvenile Orion:
A trading card game and shōjo manga series. A spin-off of the Aquarian Age franchise, the story revolves around male characters with supernatural powers.

3. Demon Diary:
"Diary of a Demon King") is a 7-volume soonjung manhwa (Korean comic) illustrated by Kara. "Kara" is the name of the duo team consisting of Kim Yoon-gyeong and Jeong Eun-sook. The name Kara is taken from the Hebrew Bible - Jeremiah 35:17 - and it means "to invite". Demon Diary was originally published by Sigongsa and has been licensed in North America by Tokyopop. In Scandinavia, it was published by Mangismo between 2005-2006.

A number of writers have worked with Kara on the production of Demon Diary. The story for volume 1 was written by Lee Chi-hyong. Lee stopped writing, because he had to prepare for the upcoming high school exams. The stories for volumes 2 through 7 were written by Lee Yun-hee.

4. Demon Flowers:
Also known as Kuruizaki no Hana. This is a horror shōnen-ai manga by Hakase Mizuki. Long ago, when Japanese Gods descended upon humans, their mixed offspring inherited supernatural powers...and the name "Kuruizaki no Hana."Now, those of the Demon world are rising up to wipe out these offspring—led by the cool and confident assassin, Ushitora. He's worshipped as a deadly professional, but when he falls in love with one such gifted boy, Masato, everything changes. Ushitora betrays his people, instead sacrificing himself to a life on the run, in order to care for Masato and a spirited orphaned girl named Nao. From Mizuki Hakase, creator of The Demon Ororon series, comes a dark, chaotic drama about three lost souls in search of the true meaning of family.

Four volumes of the story are published in English by Tokyopop

5. Dragon Knights :
This is a manga series drawn by Mineko Ohkami and shown in the monthly Japanese magazine Wings. The manga is translated in the United States by Tokyopop. The American translation is imported to Australia by Madman Entertainment.

Dragon Knights has a large cast of characters and many overlapping subplots that all weave together to form a main story line.

Note: There are also so many others that I like that it would take forever to post them here. Anyways, I hope one of these at least catches your eyes because I've enjoyed all of these tittles and still do to this date. ^_^

-Hisaki Yuki001