So if you ever need me, call, I'll be there through it all
You're the reason I can stand tall, me and my girlfriend
The line is a double entendre. Sexually, “You’re the reason I can stand tall” can either mean his literal girlfriend is extremely attractive and can make him “stand tall” (erection), OR the relationship is a very deep and intimate relationship, essentially being Pac’s Yang to his Yin.
Alternatively, this can allude to Nas' I Gave You Power. According to Young Noble, Pac was inspired by Nas' concept about talking from a gun’s point of view. The hook basically is “I gave you power, I made you buckwild”. It’s basically saying the same thing as “You’re the reason I can stand tall”. His figurative girlfriend; his gun, is the source of his courage. It’s what makes him brave and willing to confront any obstacle.
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