Tough call. If we're going biggest in proportion to the rest of their body, as well as proven measurements, I'd say Kourtney Dash takes the cake. Her dick is legitimately massive at 9x6, and paired with her 5'3 frame it's like she's a cartoon character.
That said, pure speculation has me thinking Lana Dallas as a runner up. She is also 5'3 and she's the only tgirl I've seen where her cock basically touches her knees.
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