Talk:ミセエネン (Miseenen)/@comment-35757757-20200106014533/@comment-44719384-20200106022513

One of the top comments on the YouTube upload, by 鈴本白亜, proposes that it's a kanji MARETU made up with the radicals "廿" meaning "20 years old" (the age of majority in Japan) and the radical "未" meaning "not yet." When you put the two together, you get "not yet 20 years old," in other words, "underage" or "adolescent," as in the title of the song.