LiSA's 20th single is a double A-sided single featuring the TV series intro and outro songs from the movie version of "Demon Slayer Mugen Train Hen" that has been loved by people of all ages and has set numerous records! Following "Homura", which won the "Japan Record Award" in 2020, the intro and outro songs are once again teamed up with Yuki Kajiura! LiSA will add color to [Mugen Train] in the theatrical version and the TV anime! Limited Pressing includes a creditless footage of the intro and outro themes. The content of the Regular Edition and Limited Pressing are the same.