I mean it started with the rose petal, ended with the stem
The relationship started out beautiful (like a rose petal) and ended dull and boring (like a stem). This stem (as all rose stems are) also has thorns. Thus, ending with the stem is symbolic for how their relationship has finally came to the point where each other’s flaws are beginning to show. This is where they begin to hurt each other, unintentionally.
This also references picking petals. The rose went from full to petal-less because he was picking at it trying to figure out if she loves him or not. Roses are also one of the traditional symbols of love, hence why Big Boi uses them in this piece of imagery.
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