Mekao is an old mechanic and shipwright stationed at G-8 who takes real pride in his work. He strikes up a genuine friendship with Usopp during the G-8 Arc, and eventually helps the Straw Hat Pirates escape the base. He's also the father of Dr. Kobato.
When Usopp describes seeing something strange near the Going Merry back in Skypiea, Mekao seems ready to explain what it might've been—but Drake interrupts and pulls him away before he can say anything. Fans have theorized that Mekao, like Franky, probably knew what Usopp actually witnessed was a Klabautermann, though the series didn't confirm what those creatures were until much later during Water 7.
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