The term "Candle Queen" is mainly known as a popular song by GHOST featuring the Vocaloid GUMI. There are several interpretations of the song, but it's generally acknowledged to be about a woman who is going through a mental breakdown, represented metaphorically as a burning candle. Some interpret the candle's flame as a symbol of her mental state, slowly consuming her from the inside until nothing is left [1].
Beyond this, "Candle Queen" can also refer to someone who is obsessed with or collects candles, frequently burning them and enjoying various fragrances and designs. This usage, however, is much less common.
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