“unravel” is the opening of the anime Tokyo Ghoul (2014), about a student who becomes half-human, half-ghoul after an accident. The song is his inner scream: tell me, who is inside me? He's breaking apart, the world around him is changing, and he begs not to be found — and not to be forgotten.
TK, the singer and guitarist of the rock band Ling tosite sigure, sings it in a piercing high voice, and it became one of the most iconic anime openings ever, covered by countless fans.
It's intense and fast (B2), but its key phrases are short and repeated: 教えて (tell me), 壊れる (to break), 変わる (to change). Learn those and you'll hear the heart of the song.