The Tendou Family
Tendou Akane The Tomboy, The Uncute Fiancee
Ah, Akane...of the three Tendou girls, she is the only one who studies any martial arts. She's quite good, too. She ends up being the one engaged to Ranma, something agreed upon by her sisters Nabiki and Kasumi since she "hates boys, and Ranma is only half a boy." She is a tomboy herself, though, and is frequently accused of being an "uncute tomboy" by Ranma (to which she usually attacks Ranma for). She also has this special talent for pulling mallets out of thin air.... She has no "feminine skills" (cooking, cleaning, other housekeeping chores). In fact, her cooking is so toxic that she rarely can boil water without hurting anyone. She somehow keeps on stumbling into Ranma (oft as Ranma-chan) at very bad times, which makes her believe that he's incredibly hentai (perverted). She is the youngest of the daughters.
Tendou Nabiki Nabs, The Cutest Mercenary You'll Ever Find
Nabiki cares about one thing: money. Okay, two--her family as well. She could give classes on extortion and blackmail.... One of her favorite money-making schemes is to take rather risque pictures of Ranma-chan and (less frequently and less compromising) Akane and then selling them to Kunou Tatewaki (who is in love with those two). It's rumored that she's the reason that the Tendou Dojo of Anything Goes Martial Arts is still up, with the Tendou family and two freeloaders living with no seeming visible means of support. Nabiki also has the talent of finagling free meals from Kunou and eating a lot without gaining any weight, ever. She is the middle daughter.
Tendou Kasumi The Sweet, Oblivious One
Kasumi is sweet, loving, and seemingly oblivious. Her trademark phrase is "Oh, my...." It seems as if she could never be brought down by anything. But beneath the cheerful exterior... well, it's not like she's evil inside, but she's far smarter than she seems. She and Nabiki are always plotting to keep Akane and Ranma together. (She was also astute enough to see right through one of Nabiki's schemes, where Nabiki pretended to fall in love with Ranma.) She does most of the cooking, cleaning, and other chores very well--fortunate, considering Akane's inabilities in those areas and Nabiki's sheer lack of interest. Kasumi is the eldest daughter.
Tendou Soun The Crybaby
This is the head of the household (ostensibly). Soun is very over-emotional, and easily breaks into tears or an extreme rage (the latter particularly over Ranma's other fiancees). He and Genma have been friends and partners in training for martial arts over the years, and they two are the ones who arranged for a betrothal of Ranma to one of the Tendou daughters.
Soun's wife, mother of the three girls. She died when the girls were very young, about ten years before the start of the series. Her role as housewife were quickly taken over by Kasumi. Soun still mourns her death. (I'm not really sure about her name; this is what I've heard of....)