Now I know obviously there are a lot of this, but I'm looking for specific ones. I want ones where basically the girl likes the guy & date, but either keeps it a secret or outright denies it when brought up by others. Maybe the unpopular guy is nerdy. Maybe that causes misunderstandings in their relationship and that hurts the guy, but she does love him. Also, if any have a popular boy competing for her in a love triangle then that would be great. It would cause conflict and misunderstandings between the unpopular guy and popular girl.

May not fit completely

Banken Hero - Female lead is tough and the male lead is insecure because he thinks that there is nothing he can do for her. This is only a oneshot though and I don't think it fits what you're asking for perfectly.

Witch Craft Works - Female lead is very popular and the male lead isn't. So that fits . . . I've only read 4 chapters though so I'm not sure exactly where this one goes as far as their relationship. It is also part of the Action genre so it may not even focus on romance (although it does have Romance as one of its genres as well).

Iris Zero - I've read 7 chapters of this so I can't say with full confidence that it matches what you're asking for precisely, however, I'm fairly certain that it matches most of what you're asking for.

Baby Steps - The male lead is very intelligent and hard-working, albeit a little plain in appearance. I'm not sure if there's a whole lot of romance or relationship development though because I've only read 45 chapters (though that should be enough to assume that there won't be a lot of it). Romance is one of its genres though and so that's why I'm putting it here just in case.

Koisome Momiji - I'm pretty sure this fits, however, I've only read 11 chapters so I'm not completely sure . . . meaning that it might not develop the relationship very much (but maybe it will).

Kimi wa Midara na Boku no Joou - This one fits quite a lot, however, it's definitely more erotic than others I'm recommending.

Horimiya - This fits at first, however, the male lead becomes popular in mid-to-late series. Still really good though.

RaButa - Really good despite only being a oneshot.

Fits what you're asking for much better

Kusumi-kun, Kuuki Yometemasu ka?

Hibi Chouchou

Ojojojo - The female lead isn't really popular, however, she's beautiful and rich. Also, this series is really funny and generally amazing.

Edit

Yanagida-kun to Mizuno-san - This one also fits pretty well, however, it's Hentai. Just thought I'd add it because it's pretty spot-on to what you're asking for despite being an ero-manga

Quote from re_netero

May not fit completely

Banken Hero - Female lead is tough and the male lead is insecure because he thinks that there is nothing he can do for her. This is only a oneshot though and I don't think it fits what you're asking for perfectly.

Witch Craft Works - Female lead is very popular and the male ...

I tend to wait until a series is finished so I've added most of them to my list. Thanks.

Yanagida-kun to Mizuno-san is probably one of my favorite ero-mangas.

If you have any more, please don't hesitate to post them. Thanks.

None of these fit perfectly, but you might want to read them.

Oh! Lord Jesus
Kawaii Hito (SAITOU Ken)
Otokonoko ni Toriko
Saruyama
3D Kanojo
Otoko no ko ni Kusari

Sorry that I couldn't be much of a help.

** Shoujo & Romance Manga Lover || Cleaner-Typesetter**
[img]http://i.imgur.com/5h6vq7w.gif[/img]

This sorta fits.

Love Lucky - Normal guy married Super Idol. She doesn't want to keep their marriage a secret, but they have to because her company tells her if she doesn't they get divorced.