Ouran Koukou Host Club (Ouran High School Host Club), is a manga series by Bisco Hatori that ran in LaLa magazine from 2002 to 2010. The series is complete and has been collected into 18 volumes, and was licensed by Viz in English. The series was adapted into a one season anime consisting of 26 episodes that aired in 2006. And finally, there is also a live action drama and movie that began airing in 2011.
Fujioka Haruhi is a scholarship student at the prestigious Ouran Academy. One day, she is looking for a quiet place to study and enters the Third Music Room, a place she is hoping is unoccupied. Instead, she finds the Host Club - a group of six male students who use the room to entertain the female students of the school. During this encounter, Haruhi manages to break a very expensive vase, and becomes a member of the Host Club to replay the debt. And due to some ambiguity about her gender, the school believes she is a male.
Ouran is a very fun series that pokes fun at a lot of shoujo tropes. It has a colourful cast of characters that are all well developed and interesting, and Haruhi is one of my favourite shoujo heroines. It's a series I recommend in any form, but particularly the manga (just for the full story). While Haruhi, the poor scholarship student, is thrust into the extravagant world of the Host Club, the other hosts are fascinated by her "commoner" ways. Haruhi forms relationships with each of the boys, and she becomes very important to the Host Club.
Haruhi is a refreshing heroine to have in a shoujo. She's quietly confident in herself - not arrogant by any means, but she has a self assurance that is often lacking in shoujo heroines. Her attitude is straightforward - sometimes blunt - but never cruel or mean. Haruhi is a kind person, and she's hardworking and intelligent - after all, she got into the Ouran academy on scholarship and manages to retain her place. Haruhi is also, despite coming across at times as being indifferent or apathetic, quite selfless. She will prioritise others over her own feelings and is perceptive to the emotions of others (although not so much when it comes to her own emotions). That's probably why, in part, she's such a good - and natural - host.
When she first meets the Host Club, Haruhi isn't impressed by their good looks or wealth - for her the exterior isn't as important as what's on the inside. She sees all of them as real people with faults and goodness in them, and not just as whatever "type" they sell themselves as when they're hosting.
I also do love her reactions to some of the Host Club's actions - Haruhi is the sensible voice of reason most of the time!