I'm Shamu with twelve pair
from Lupe Fiasco – Failure Lyrics on Rap Genius
Meaning
Shamu is a famous whale at Sea World in Florida

By “12 pair” he means lungs! (not testicles)
Also means he now has 12 pairs of sneakers.
Adding on the “Coming up for airs” Shamu can comes up for air more frequently and does it in a more flashy fashion = More and better sneakers
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