Looking for mature Seinen/Josei Romance manga
 

The title more or less says it all. It can be mature, or not, I don't really care. But No yaoi or shoujo-ai, please. Not that I'm homophobic, but I can't identify well with the characters, thus the story's drama ends up being lost on me.

I'd like the story to revolve around the romance mainly, though if it has an exceptionally good storyline, I'm willing to at least give it a try.

And although I said Seinen/Josei in the title, it doesn't necessarily have to be. I'm also willing to read Shounen/Shoujo manga romances as well, though I find they don't have as much dramatic tension as I like in stories.

I'm also open to manwha.

My only real restriction (for Shoujo/Josei, mainly) is I don't like timid female protagonists with tons of self-esteem issues. I've read a few manga that I've liked that had heroines like that, but they do tend to annoy me. It's bad enough with timid male protagonists, but the female protagonists like this are even worse, often times.

An example of some similar manga I've read/started and enjoyed:

3.3.7. Byooshi
Dance in the Vampire Bund
Desire Climax
GE - Good Ending
Honeymoon Salad
Immortal Regis/Cavalier of the Abyss
Koibana Onsen
Love Junkies
Parallel
REC
Sakura Tsuushin
Sundome
Tasogare Otome X Amnesia

A few manga I've been considering but haven't starting reading in earnest yet:

IO
Kaikan Phrase
Onidere
Pastel
Skip Beat (heard this one is really good, recommendations for yea/nay would be appreciated)
Velvet Kiss


Anyway, any suggestions at all would be appreciated. I just got into reading romance a few months ago, so I'm really not sure what kind of good romances are out there. Thanks a lot guys.

This seems to play out more like a romantic comedy than a straightforward romance, but Nodame Cantabile would be a nice one to go with on the Josei side. For seinen, since you didn't seem to mind the provocativeness of Vampire Bund, then Chobits is my second bet. Finally, there's Kare Kano, which has a very strong-willed female lead.

Firstly Skip Beat is not mature; it is Shoujo.

Secondly, while I have not caught up with the latest for a long time (about a year or so), it is really interesting. Because it's not totally focused on romance, but pretty balanced overall. And the most interesting part for me is the development of the protagonist as an actress. The acting parts and skills and techniques detailed in the manga are really, really interesting. You don't need to worry about timid characters, because both female and male leads (as well as his rivals) have strong personalities and the protagonist herself is a very strong willed character (it's almost like reading reverse shounen with romance elements), though you may not find it so in the first chapter ;). To top it off, it can be extremely humorous. :D That's why I say it's pretty balanced. I'm a guy who doesn't normally like to read shoujo, but I absolutely love this manga.

While technically shoujo with a teenaged central cast, I think Sand Chronicles is quite mature - in fact, some argue that it's actually Josei, especially in later stages. It's quite complex and layered, with some very real depth of emotion.

Thanks for the suggestions, guys.

I've already read Chobits. I liked it, and the anime as well. I'll definitely check out Kare Kano.

I'll check out Sand Chronicles as well. Sounds right up my alley.

Silver by Fujita Kazuko (lead girl starts off with no backbone, but she gets one)
Boku no Hatsukoi wa Kimi ni Sasagu

Yume de Aetera. It is a seinen. Main character loves a woman. Tries his best to impress her. Many mishaps along the way.

Have you read Little House with an Orange Roof? It's a mature romance between two single parents who is forced to live together (with their children, of course) coz they got scammed by a property conman. Although the background setting is hilarious, it's not a hilarious manga. In fact, it's more about everyday live/romance with mature tone. Still, I don't know if you like romance between grown-up divorced parents though, but the story is solid.