悪いことはしちゃいけないよ (Warui Koto wa Shicha Ikenai yo)

Background
This song is one of Kikuo's most popular songs. The lyrics are vague and open to interpretation, although popular interpretations include themes like child abuse, bullying, or a dead child warning other children not to do bad things so they won't end up dead like her; another popular one is human/child trafficking. The song is featured on Kikuo's first album KikuoMiku.