Rikka Matsuura

Rikka Matsuura is the younger half-sister of Miki Koishikawa and Yuu Matsuura. Her parents are Youji and Rumi Matsuura.

Physical appearance
Rikka resembles Miki except her hair is longer and brown instead of red.

Personality and traits
Rikka's personality is similar to Miki's when she (Miki) was younger. Rikka isn't academically smart and was at the bottom of their class. She is cheerful just like her older sister.

Saku Koishikawa
Hajime is Rikka's step-brother. She and Saku aren't blood-related but we’re raised as siblings. They have shared a close bond since they were born and, unbeknownst to Rikka, Saku had feelings for her. When he admitted his feelings to her, Rikka didn’t reciprocate them due to their upbringing as siblings. However, she gradually starts to see Saku as more of a boy than a brother, and they fall in love. They later begin to secretly date. At the end of Marmalade Boy Little, they confess to their family about their relationship and their parents and siblings accept it.

Aoi Namura
Meiko and Namura's son. After giving her his umbrella during a storm after school one day she develops a crush on him. She was heartbroken to learn he had a girlfriend but after getting dumped, he develops feelings for Rikka and they go out for a bit. They eventually decide to remain friends when Rikka realizes she likes Saku.

Emiri
Rikka and Saori were always seen walking together. She is Rika's friend who's in the same class as her. Emiri offers Rikka support as she struggles with her feelings for Saku and Aoi. They have a brief falling out when Emiri’s crush, Koudai, starts to like Rikka. However, the two friends patch things up when Rikka shows she isn’t interested in Koudai.

Rena Sasamiya
Rikka envied Rena for her beauty. She was surprised to hear Rena liked Saku, who was only interested in Rikka, which made Rena jealous and determined to win Saku’s heart. The two girls became close friends, even when Rena finally gives up Saku when she develops feelings for Aoi.

Miki Koishikawa
Miki is Rikka's older half-sister from her mother's side.

Yuu Matsuura
Yuu is Rikka's older half-brother from her father's side.

Youji Matsuura
Youji is Rikka's biological father.

Rumi Matsuura
Rumi is Rikka's biological mother.

Ginta Suou
Ginta is Rikka's teacher at Toryo High. She and Ginta appeared to be close. Ginta told her the story about Yuu, Miki, and him and that he used to have a crush on her older sister. She calls Ginta "Gin-chan" just like how Miki and Ginta called Namura "Na-chan."

Jin Koishikawa
Rikka saw Jin as her real father.

Chiyako Koishikawa
Even though she and Chiyako weren't related, she still saw Chiyako as her mother.

Appearances

 * Marmalade Boy Little
 * Chapter 1