Merge the mixture with the purest and the fruits
And the thirst just the worst it's the curse of the juice
Chance is referring about the whole song itself, its a mixture of his pure intent and his exotic taste in music AKA the fruit. The last line is a comparison to this song again, just like when you drink really good juice you get thirsty after a while and want to drink the juice again, once you hear this song you literally want to listen to Juice again!
Its also saying girls/people/haters in general are thirsty when you have the “JUICE” meaning the power, fame, limelight, etc.
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