I was thinking the same lol I think the author made it unnecessarily huge lolol
Look at the angle of the drawing. It's viewed from below (which is why his thighs also look so big) and his penis is closer to the "camera" than any other part of his body. This is a trick known as "forced perspective" that makes objects look bigger (or smaller). Also, some of that size is the aura of the "glow". Or...
... it's your typical sextoon, with an over-exaggerated drawn body part on a crazy rich, wildly attractive and physically well-built man, who's also an honest, fair CEO who looks out for the underdog.
So yeah, nothing realistic about this at all. Which is how I like my fictional characters.
Hahaha no thank you! I don't like porn
Right?
That's a unrealistic dick size