I'm also interested in something with this plot.
I've got a couple suggestion too
First I second practically everything here, as most I have read or have on my wish list as I await more chapters. But I want to add
Love so Life as it is adorable (but not in a way that's too sugary which is nice) also I think [m]Skip Beat[/m] fits though we're 150+ chapters in and there's not really any romantic development but it still doesn't feel dragged out. However with Skip Beat I find it's a better read when you have a lot of chapters, reading a chapter and then waiting the next, personally, I loose interest because sometimes not a hell of a lot happens in one chapter.
Mars someone all ready suggested but I've got to put my two cents in because it's one of my favourite mangas, granted it is dramatic - it really is your typical popular bad boy meets innocent introverted good girl type story and all the drama that comes with it. Another dramatic one but with what I thought was a well developed relationship was
Cipher.
Off the top of my head also, though I'm not sure they fit exactly:
[m]Ashita no Ojousama[/m] - josei and romance isn't the main plot, about an aspiring playwrite who develops a friendship and with a popular actor
Land of the Blindfolded - sort of love triangle-y but not in a bad way. Been a while since I read it but if I recall she has supernatural powers and meets two guys who also have them - hilarity like only shoujo can do ensues
Sora Log - cute somewhat innocent happy-go-lucky sort of girl who loves stargazing befriends the school bad boy
Hotaru no Hikari - there's a sort of love triangle on the go, she's dating a younger guy but living with her boss due to certain circumstances. Honestly I prefer the friendship she has with her boss to the romance so far...
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