Blue Heaven
Sanctuary

Hrodulf and Bjornolfr, you will not be forgotten.
[img]http://i411.photobucket.com/albums/pp199/SyberAngelGabrielle/couplesig.jpg[/img]
[color=black]And if the world were black and white,
you would be my rainbow in shades of grey.[/color]

Click 'n Play!

If I had a fantasy self, it'd be a tentacle monster.

Dogs

This entire series is worth reading hahaha.

[img]http://www.nodiatis.com/pub/21.jpg[/img]

One comes to mind:
Threads of time
...oh and Kiseijuu =D

"Flying is learning how to throw yourself at the ground and miss." - Douglas Adams

Manga/Animelist

Densha Otoko - Net Hatsu, Kakueki Teisha no Love Story
Adventure Boys

they're not too bad.

Common sense just isn't that common

Until Death Do Us Part
Lunar Legend Tsukihime
Doujin Work
Honeymoon Salad
Koe de Oshigoto!
Seikon no Quasar
Saru Lock
Fugurumakan Raihouki
Hoshi no Koe
Happiness (FURUYA Usamaru)
Inubaka

Hmm, I think all of these have some kind of romance. Oh well. They're all good anyway.
edit: No ecchi? That kills like...all of my recs 🤢

"I've seen a look in dogs' eyes, a quickly vanishing look of amazed contempt, and I am convinced that basically dogs think humans are nuts." -John Steinbeck

These are some of the seinen I would recommend, all different in their own way. Hope you find what you need.

The Breaker
Parasyte
IO
Initial D
Holyland
Iryuu - Team Medical Dragon
Jormungand
Liar Game
Sun-Ken Rock
Tough
Vinland Saga
Zero

I already read parasyte, vinland saga, i dropped until death do us part cause the story was getting boring. Densha Otoko <--- read it already (pretty good tho). I'll had 1 more request... try to leave ecchiness out of the thread, since i think its really weird and only makes mangas look childish and immature.

Thx a lot for the suggestions

Historie
Black Lagoon
Elfen Lied
Alive!
and
Ichi The Killer.

Also, Bio-Meat: Nectar Is a Shounen with a Seinen type of feel about it.

Does the walker choose the path, or the path the walker?

You listed Ciguatera, so I recommend Himizu, by the same author. Less happy, but a literary gem. I'll also pimp Lucifer and the Biscuit Hammer (listed as ecchi, but it's not... just has some non-gratuitous underwear moments), as I enjoy it greatly. Piano no Mori trumps them all, though... give it a chance and you'll love it forever.

And so I'm not only mentioning my own projects, I'll second Historie and I'm not sure if Mysterious Girlfriend X was mentioned, but I enjoy that when I'm in the mood.

Quote from NightSwan

Here are some titles. Some have romance... Maybe you'd like those~

Blame!
Blood Alone
Emma and the great sequel Emma Bangaihen
Hourou Musuko
Iryuu - Team Medical Dragon
Yokohama Kaidashi Kikou
My Girl (SAHARA Mizu)
Wild Adapter
Bus Hashiru
Ichi the Killer
Hoshi no Koe

Edit:

A oneshot: Dirty Work.

I second Blood Alone, it's awesome.

As for a romance Seinen:

Cherry by Kubonouchi Eisaku. Something about that series really captivated me.

Maybe some1 knows a good seinen manga with a decent amount of action...(Not 1 that was already said.plz)

Thx for the suggestions everybody