Cause I'm outta this world girl, I got that Milky Way dick vein
This line is a reference to the Milky Way candy bar. Older ads had the tagline “Out of this world”. The “Milky Way dick vein” is the “swirl” of chocolate on top of the candy bar which looks like the veins on his dick.
The Milky Way is a galaxy of stars in space, hence “out of this world”, and semen is white like milk. Therefore, his penis has a “Milky Way dick vein” for being out of this world good and able to produce copious amounts of semen.
And also a Milky Way bar has a big vein of caramel running through the top of it, like a dick gets when its really hard. Also, Royce’s would be the same color as the candy bar.
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