Malhonnête means "dishonest" or "insincere." It's a strong word that isn't used in everyday conversation or every song, making it stand out.
In the song, the singer admits, "Te dire que je n'veux pas te détourner serait malhonnête" (To tell you I don't want to turn you away would be dishonest). This reveals his true intentions despite the woman having a boyfriend, adding a layer of intriguing complexity to his character and the song's narrative.
Colonel Reyel's "Celui" is a bold and direct declaration of love and desire, even when the odds are stacked against him! From the moment the day begins, he can't get this person out of his head: "Aussitôt que le jour se lève tu es dans ma tête" [As soon as the day breaks, you are in my head]. He knows she has a boyfriend and is committed to him, but that doesn't stop him from wanting to be "celui qui partage ta vie" [the one who shares your life].
He's pretty blunt about wanting to be the one she confides in, believing no one could understand her better than him. He even offers a backup plan, saying "Au pire, celui qui partage ta nuit" [At worst, the one who shares your night] if a full relationship isn't possible. It's a mix of sincere affection and a touch of playful urgency, as he imagines grand trips to Miami or Brazil, only to realize he doesn't even have her number yet! He's ready to be "celui qui brave tes interdits" [the one who defies your prohibitions], showing just how much he wants to be with her.