This isn't the best manga in the world, but it is soft and sweet if you need something simple to read. I do want to point out, however, that it's label as a 'romance' is completely wrong and should be changed. It IS a shojo manga, but it is not a romance. It's more of a 'family' manga and focuses around a family aspect.
If you go in looking for any romance, you'll be sorely dissapointed, for it is NOT that kind of manga.
Now that I got that out of the way, the concept is that the main lead female lost her mother, and learns that her father is the king of some far off european country, who sent two butlers to watch over her. It shows their progress of being her butlers to becoming genuinely important family members to her.
All aspects are soft and sweet, and it's just supposed to be a feel-good manga, never delving too deep into major plot-aspects. Which can be it's downfall, as it has a lot of wide-open doors that they never explore, that should have been.
So if you go in, not expecting a large ammount of plot, and just wanting something short, soft and sweet, then this is the manga that you should definately read as a sweet family-oriented manga.
Hope this helps.