“25” fits the theme of the album well, as singer Taylor Momsen chronicles her life in the context of Rock and Roll and her own idolization of rock stars in her teens. She also references the Club 27, as she already did in the first single “Death by Rock and Roll”.

She talks about the first little experiences with sexuality (“Five to six, a lie, a kiss”) which ultimately repeated themselves a little later on (“Ten, we’re here again”).

Momsen is known to be a lover of the Rock and Roll genre and she seems to have idolized rock stars in her teens. In typical dramatic and rebellious fashion, she had thoughts about imitating the death of her idols at 27. Many rock stars have perished at that age, leading to the formation of the infamous Club 27 (“And all through my teens, I screamed that may not live much past”).

Momsen was indeed twenty-five years old when she wrote the song. She confirmed that in an interview with Blabbermouth published on November 13, 2020.
The chorus talks about her still being alive at that age and that it seems to become apparent that she will not die at twenty-seven.