When Luffy sets out to start the Straw Hat Pirates, his first goal is to gather a crew. The way Luffy manages to get crew members tends to vary, though it’s not unusual for Luffy to offer a prospect a position and simply act as if they’ve accepted even if they haven’t. His inspirational personality, simple-mindedness, and strength all lend themselves to convincing people to join him. Zoro, the first member to join the Straw Hat Pirates, was made to join in such a fashion when Luffy saves him from execution and they unite to dethrone a local Navy captain.

In other instances, Luffy has offered his friendship and a place among the Straw Hat Pirates to people he wasn’t familiar with simply because they were interesting. For example, Luffy couldn’t help but ask Brooks, an undead musician, to join his crew and Brooks immediately accepted the offer despite the dismay of the rest of the Straw Hat crew. Luffy has extended that same offer to other people who wouldn’t necessarily have fit in or had any significant role, although they never developed into an actual entry into the Straw Hat Pirates.

The Straw Hat Pirates’ relationship has developed throughout the series’ more than 800 episodes and, although some crew members have attempted to leave, Luffy’s bond with them has ensured those were never permanent departures. They’ve all come to respect him and to trust his judgment, no matter how simple-minded it may be. It’s safe to say that Luffy’s relationship with the Straw Hat Pirates is as friendly as it is familial and he’s willing to do anything to protect them and keep them by his side.

The list of creatures and people Luffy has met and befriended across his adventures is endless. Luffy has a way of making friends out of nearly everyone he meets and immediately aligning himself with their cause. This easy attachment has led the Straw Hat Pirates on all sorts of adventures away from their intended goals. After meeting Princess Vivi, who was going under the name of Miss Wednesday to infiltrate a criminal organization that had taken over her country, Luffy decides to help her save the kingdom without having built much of a friendship with her. It may simply be a case of Luffy being a good judge of character or because he enjoys the prospect of a grand adventure, but Luffy has a history of building these friendships on a whim, and usually, it pays off.

Despite being quick to make friends, Luffy values each friendship he’s made across his adventures. One Piece is notorious for rarely ever having deaths, but the few deaths or allusions to death there have been have shaken Luffy to his very core. His first experience of loss was in his childhood when one of his friends, Sabo, was seemingly killed while running away from his family. The loss profoundly marked Luffy and he was determined to never lose anyone ever again.

Unfortunately, he was faced with another loss when Ace, a friend he regarded as a brother, was sentenced to death. Luffy infiltrated a jail, sacrificed limb and life, fought an army, faced off against the Seven Warlords, the Admirals, and even his grandfather to save Ace. He finally succeeded, and just as they were about to escape, Ace sacrificed himself to save Luffy from Akainu, one of the admirals. The shock of seeing another dear friend die was too much for Luffy, he was so overcome with grief that he had a mental breakdown. It was only through the help of some of the friends he’d made over the years that he was able to remember that he still had all his friends in the Straw Hat Pirates.