Royaume means "kingdom". While the word itself is not rare, its use in this song is what makes it so special and poetic.
Indila sings, "J'ai toute ma peine comme royaume" (I have all my sorrow as my kingdom). This powerful metaphor paints a picture of her sadness being so vast and all-encompassing that it has become the entire world she rules over, highlighting the song's theme of profound loneliness and isolation.
French singer Indila wastes zero time on subtle hints here: right from the jump, she is sending an emergency distress signal into the void. The chorus hits hard with "C'est un SOS, je suis touchée je suis à terre" ("It's an SOS, I'm hit, I'm on the ground") and asks the empty room, "y'a t-il quelqu'un" ("is there anyone there"). In French, saying you are à terre literally means knocked down to the dirt, but here it speaks to complete exhaustion. She walks away from everything because she felt detached from her own identity—"je n'étais plus moi" ("I wasn't myself anymore")—only to end up invisible, fighting what she calls the cold and the void.
What makes this track stand out is its dramatic, almost theatrical solitude. She declares herself royalty over her own misery with the line "J'ai toute ma peine comme royaume" ("I have all my sorrow as a kingdom"). Yet, right next to that melodramatic kingdom, she spots hope through prison bars: "Voir la lumière entre les barreaux / Et regarder comme le ciel est beau" ("Seeing the light between the bars / And looking at how beautiful the sky is"). She feels reduced to "un objet sans éclat" ("an object without shine" or an unpolished, dull object, using éclat to mean radiance or spark). Even when she feels like a total nobody, her voice keeps calling out across the distance to make sure someone, somewhere, is listening.