Hello! I'm looking for a manga that makes you read chapter after chapter to see how the story develops. The kind of manga that you complete in one or two days.
Only things I would like to avoid if possible is shoujos and the typical loong and with fillers shounen (Naruto, Bleach kind).
Thanks in advance!

You've sort of just described ANY manga that isn't bad. Or shoujo.

Hahahaha, I guess you are right. Let's see, something along the lines of Berserk, Monster, Tower of God, Aku no Hana for example. Something serious and with a good development and length. Monster is soo good.

Bitter Virgin - impossible to put down, finished it in one night.

Doubutsu no Kuni

Jisatsutou-ongoing
Vinland Saga-ongoing
Akumetsu-completed.

All these are serious and have good development!

Hoshi no Samidare

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in need of romance?
uncommon, sad, sweet

I have recently taken a liking to Basara and Tokyo Crazy Paradise. Though both have a shoujo tag both are more focused on battles (TCP has more shoujo).
And I don't know if it matters but both are an older style of art and both are complete.
Both are long 90+ & 76 chapters respectively.
Both are worth a try even if you don't care for shoujo, neither follow the typical shoujo flow.

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I'm sorry for my long comments... So much stuff going through my head and I think I should share all of it with the world!
Plus, learning other people's opinions of the things I say is addictive to me.

KNOWLEDGE & NONSENSE... It makes the world go round <3

Alright! Thanks everybody! I will make sure to check them out

20th Century Boys

Do yourself a favor and read it.

Vampire Juujikai

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Is this me in a nutshell?
Pretty much.