A rather cheerful and gentle girl who has leukemia. She lives at a local hospital and acts as an older sister figure towards the other children there. She is the childhood friend and secret lover of Makoto Jinguu. He wishes to marry her, but won't until a donor is found whose bone marrow is compatible with Ruriko's body. Because such a donor is rare, Makoto wanted to rise up in the political world so that he could become the prime minister and issue a law that would make everyone in Japan donate their bone marrow. After Gin and Kirara collaborate to hold a special concert exclusively for all of Kirara's fans that would agree to donate their bone marrows, it is revealed in the last chapter of the main story that a suitable donor was found and that Ruriko was currently undergoing treatment.
