A character with an arrogant, bossy attitude, often rich and with some princess-like heritage.
When you hear this kind of laugh, you know what kind of character you're dealing with. Could be divided in to two cases, first being this: the overbearing, hyper character, complete with her drill-like curved blonde hair, and the laugh you see above. Often just used as a comical aproach on to the 'commoner's world', they have the money, they have the statue, and they want to show it off to you. Often stirred with some tsundere personality. Also has the Tsurime eyes.
The second type is it's näive counterpart. She is the the daughter of some powerful family, or just the school idol - blessed upon by the many students the school has. Whichever is, she is protected against the many evil in the world with fanaticism by the family/students. Their personality might be that of a Yamato Nadeshiko, but they still carry the arrogancy typical of ojou characters - not because they want to, but because of obliviousness to what the 'commoner's world' has to offer. In contrast, they have the Tareme eyes.
For an extra note, they both can have some classy-like talking; adding '~desu wa~' (pitch up the tone at the wa~ part) at the end of their sentences, saying 'watakushi' for 'watashi' while refering to themselves.
The title of Ojou is a derivative of the term Ojousama (お嬢さま). Ojou is technically the word used to mean "someone's daughter". It can be used as a Honorific in the Japanese language to refer to a woman or girl from high social standing. (i.e. a princess or the daughter or a wealthy family)