They are my Noble Masters is ecchi harem with a great story. That pretty much sums it up and if any of you out there have watched a lot of harem, you'll know it's a rare thing when it has a story at all. What was great about this anime is that the story doesn't apologize for itself - it is what it is. The eldest sister, Shinra, is a weird cross between a tsundere and a deredere with potent perverted instincs. She's so unique, that she alone is worth watching this series.
But the supporting cast minus maybe one or two characters are all well-developed and you find you know them intimiately by the end of the series, which is another rare thing. The theme of this story is essentially this trio of rich sisters who lost their parents, taking on delinquents or orphans like them to become their butlers and make them a part of their family. And what's great is that this anime never loses that theme, not for a moment. Most anime will introduce a theme and then forget it two episode in in order to dispense with the cliched nuances of harem anime. So, by remembering the theme, this anime accomplishes so much. I wanted 30 more episodes of this anime simply for that reason. It was refreshing and I fell in love with the people.
There were some minor problems. The relationship between Shinra and Ren could have been developed more, but the animators chose to put it off most of the time in order to stuff each episode with Shinra basically molesting her chief maid and her lolita-looking younger sister. It wasn't bad (it was very good, if you get me. hehe), but romantics might be a little disppointed until the last episode. Also, as mentioned before, this series was just too short, but it's because it was so good. So it's a win/lose proposition.
I would recommend this to any guy. (I just don't see how girls could enjoy this.) It's certainly among the best out there and considering it was released in 2008, I'll have my fingers crossed for a second season.