The childhood sweetheart of Jinta Yadomi, Menma had a tragic death that ultimately split up her group of friends. She reappears years later as a specter to reunite the five teenagers, who are unable to forget about her.
Although she is aware of her death, she is talkative and lively. She greatly values the childhood memories and friendship she once shared with the others, and has very few memories other than recollections of her friends and family, including that she had once made a request to Jinta. When she appears to Jinta, she has aged somewhat, but still retains childlike speech patterns and tendencies. She is also clothed in the dress she was wearing the day that she died and she doesn't wear shoes/sandals. Though only Jinta has the ability to see or hear her, Meiko appears to be able to interact with the world around her: opening doors, cooking food, eating, and even playing video games, with many of these activities shown in scenes without Jinta present. Characters that she embraces often feel that the air is heavier. The others call her by her childhood nickname 'Menma', and she similarly refers to the Super Peace Busters by their childhood nicknames. Jinta has stated that she is selfless, only crying when others are hurt. Meiko holds no grudges towards her friends for the accident. She hopes to pass on to heaven so that she can be reincarnated and once more be in the same world as her friends. She is of mixed Russian and Japanese ancestry.