Soun and Genma trained during their youths with the evil and perverted Happosai. The little man is THE master of Anything Goes Martial arts (Musabetsu Kakut� Ryū). He is also a panty theif and lecher beyond belief. In return for training, he berated and cajolled his two unwilling students into helping him with his panty raids and peeping expiditions. More often than not, they would end up humiliated or injured in the process. Once they had finally finished their training (ie: escaped) they were able to get on with their lives. That is, until Happosai returned to select the next Anything Goes master. What he found when he reached the Tendou Dojo was Ranma. Disgustingly enough, Happosai leched onto girl-type Ranma, even though he knows Ranma is a boy. Taking up residence at the Tendou Dojo, he began extending Ranma's training. He also began to expand his panty raids into the surrounding neighborhood, as well as the Tendou girls' bedrooms. Happosai is a tiny, yet immensely powerful martial artist. He usually wears a purple coverall, or occasionally a green bathing suit. When on his panty raids, he often wears a scarf as a mask. He is bald, with white fringes and a white moustache. Happosai is a master martial artist and deceptively strong for his size. His only real weakness is his perverted nature. Happosai would leap in front of a speeding train for a pair of girl's panties. Often times he is foiled by a well placed bra, and if he cannot lech onto some poor, unsuspecting girl, or Ranma, he goes into an addict's withdrawl syndrome. His power comes entirely from his lust, and can be easily defeated by denying it. Happosai is master of many magical martial arts attacks, although many are really just special effects. For example, his world feared 'Happo-dai-karin' (Happo Fire Blast) Technique is really just a firework and a match. He does however, posess several powerful special energy techniques, as well. SOURCE: http://www.geocities.com/Tokyo/Garden/7950/Happy.htm
Takaaki is the main male character. Takaaki is childhood friends with Konomi and sees her as a younger sister. In the anime, it is noted that he has an aversion to most girls save for Konomi and Tamaki, mainly because of their childhood friendship. He is a kind young man who, despite his shy nature around girls, is often very kind to them when the situation arises.
Tamaki is also childhood friends with both Konomi and Takaaki the two see her as an older sister. She left them when they were both children, having to go to an all-girls boarding school. Her promise to come back to Takaki in the final year of high school is what prompted her to leave her boarding school. She is very confident and comes from a rich family. She is well versed in traditional Japanese arts and traditions, yet still is a modern girl in her own right. In her group consisting of Konomi, Takaaki and Yuuji (Tamaki's younger brother), she is the strong and dominant personality and is acts as the older-sister figure. She often addresses herself as "Tama-oneechan".
Candidate pilot. Karin is a quiet girl who seems to be distracted from reality and likes to text-message her cell phone. She is afraid of cats in general and is 15 years old. (Source: Wikipedia)
Lunar is a childhood friend and rival of Sun. She has used the powers of her mermaid voice to become a pop star idol singer. She seems to suffer from a superiority complex, and she never passes up an attempt to overshadow Sun. She initially thought that Sun was boasting Nagasumi to her, and in an attempt to outdo Sun she decides to steal him away from her by making Nagasumi her servant, since Nagasumi has also seen her mermaid form. Later she decides to live in Nagasumi's house until his servant status is over. (Source: Wikipedia)
Kai is the richest boy in Japan, the fourteen-year-old son of the head of the multi-million dollar Mikawa Corporation. He rivals Nagasumi for Sun's hand in marriage. He is a killer whale from another mermaid group. Strangely while Sun and Lunar are shown in Mermaid form (torso of a human and tail of a fish) whenever they fail to maintain their human forms, Mikawa is shown as an entire Killer Whale when he succumbs to the effect of water. He also has agoraphobia, which is why he travels only in submarines and wears an astronaut's suit in open spaces. While looking for a servant he befriends Saru. His name is related to Mikawa Bay and Neptune (海王星, kai�sei?). (wikipedia)
Height: 148 cm Mawari is the daughter of the chief of police in Nagasumi's hometown, and a childhood friend of Nagasumi, who she has a crush on. She takes it upon herself to act as a moderator of social behavior, and often reprimands Nagasumi for some of his actions. Source - Wikipedia She is quite short compared to other females, especially Seto Sun.