First of all, none of those titles he recommended are hentai, they are borderline-H. Meaning, they actually have plot (well, some of those titles are episodic comedies). I can vouch for sure that Toshiue no Hito, Velvet Kiss, Koi wo Suru no ga Shigoto desu, and Hetakoi are all plot-driven romance manga.

Secondly, seinen is a demographic, not a genre. By that I mean the only characteristic of a seinen title is that it's published in a magazine aimed at an older male audience (ages 18-35 I think). So, while you'll undoubtedly find more violent seinen manga than josei, they're not inherently violent at all. You'll find plenty of seinen manga that are strictly romance/comedy/drama/etc that have zero violence.

For a quality seinen romance/smut manga, I'd recommend Natsu no Zenjitsu.

Sorcha and TiffanyMunro, thanks for the mangas.........and yes i've already read them too 😳 wow i wonder if i've read every smut manga out there?? is that humanly possible?

The Matrix is REAL.

vedanta, I feel like you, that either I've read every good smut manga, or have it on my 'to read' list. I have a few by YOSHIHARA Yuki, ENJOUJI Maki, and OHMI Tomu that I haven't read yet, just so I have something to look forward to.

Here's a couple I didn't see mentioned:
Ikenai Candy Love by NAGAE Tomomi, also her It's Not Like That, Darling isn't too bad, but the extra in the last volume, "Stress Pink", is really good.
Hard na Choukyoushi - cute smut by TAKADA Rie
Stroke Material, male protagonist, very funny
Mosaic Man, a oneshot
Bocchama wa Ijiwaru - I liked what there was of it, but the scanlation is stalled
Koakuma to Meromero Tengoku - a bit different from the usual, in that both protagonists aren't exactly gorgeous, but it's worth reading
Choukyouai, shorts
Four Reasons To Fall in Love With Him (Aitsu ni Koishita 4 Tsunowake), shorts. I liked the second story the most.
Lose Control is much better than the cover makes it look.
Mamotte Agemasu - not very smutty, but I really like it. Mangaka of Mitsu no Yoru, which is much smuttier.
Nemurenu Yoru wa Knock Shite
Pretty Poison
Tengoku no Mail
"Double☆Booking", a short in Uzakoi. You have to read this one.
Johyou to Chuujitsu na Geboku, story 2 is really good
Rinjin wa Chou
Honey na Koto

I hope there are some here that are new to you. The problem is, there is a lot of smut that is just not good, and I didn't want to recommend anything that I wouldn't read again myself.

thank you everyone that's given me suggestions, i really really appreciate it. there were new mangas that i never read and mangas that i've read and re-read. so what do you do after you've read all these manga? o.O'

The Matrix is REAL.

Read more manga. I would suggest expanding your literary perpsective; it's possible to read a good portion of notable titles in just one genre over the course of several years or so, but if you're interested in multiple genres, there's always something new. I would also suggest picking up more ongoing manga if you happen to be someone who only checks out completed titles.

I would agree with wafflestatus to look beyond smut. But then, I went back and re-read your original post, in which you asked for josei and romance. 😳

So I'll suggest some manga for women or girls with more mature themes, that isn't necessarily smut. Hope you like some of these, and that they are new to you.
Candy Life, by the mangaka of Kimi wa Petto, which I haven't read yet.
A Delicious Relationship (Oishii Kankei) - when I read this, it immediately became one of my favorite titles. It went in directions I didn't expect.
7 Seeds - I'm about halfway through this, and it's every bit as good as everyone says it is.
The One - the best-looking man in manga (manhua, actually), twice
Hot Gimmick
Hadashi de Bara o Fume
Paradise Kiss
Nana
Living Game - a slow seinen (for men) romance. I enjoyed it, even though it gets kind of draggy in the middle.
And a smut I forgot before, the cute oneshot Santa Claus Panic

Plus check out these threads:
Best Josei
Best Josei HUNK. <3

Thanks for replying. It's gratifying to hear back whether or not the suggestions were useful. 😃

Puppy Lovers I haven't watched it though, I don't read smut but I heard its good, Aki-Sora if you don't mind incest

Recommend me horror , yaoi and shoujo manga please 😀

While i haven't read all of these I did try making a search for you. These are ones with at least one release. good luck.
[url]http://www.mangaupdates.com/series.html?genre=Romance_Smut&exclude_genre=Hentai_Yaoi_Yuri&filter=some_releases&perpage=50[/url]