ZoLu

ZoLu is the slash ship between One Piece characters Roronoa Zoro and Monkey D. Luffy.

Canon
Zoro and Luffy are shown as having a close friendship bond. Luffy admires Zoro and Zoro views his captain as sometimes being a "pain in the ass", but still loves and respects him.

Fan Fiction
Luffy/Zoro tag on AO3

Pixiv
Zoro/Luffy on Pixiv