Bara no Tame ni(1992)

After being dumped, followed closely by her grandmother's sudden death, the chubby Yuri is left broke and homeless. That is until she discovers that her grandmother had been lying to her for years. Her mother is not dead, but is in fact a famous movie star, and very much alive.

Upon arriving at her mother's house, she meets her three new beautiful siblings, all from different fathers. Her newfound family is filled with hilarious oddities, ranging from laziness to drunkennes to gay incest. She is constantly antagonized by her brothers Sumire and Aoi. And her sister Fuyou does little to help. And thus Yuri becomes little more than a maid in the household, catering to her siblings needs while her mother travels the world.
But as Yuri's warmth fills the house which before had been so cold...what will happen between her and her brothers? Can they come to see each other as siblings before it's too late?

Note: Won the Shogakukan Manga Award for shoujo in 1994.