Mizuki Hayama

羽山 ミズキ, Miki

Mizuki goes to an affiliated school and admires Kei greatly as someone who is older than her; in fact, Mizuki is also on her school's girl's basketball team. She greatly enjoys reading shōjo manga. She has a straightforward attitude and likes to be frank towards others, especially to Kei. She's the main heroine of the fourth chapter from the ''Ef'' series: Ef -The latter tale-.

In a tale of melodies, she falls in love with Kuze, who she met as child.