Gear 5 is suspiciously similar to Brazilian Martial Fight Capoeira
Capoeira is a very free flowing type of fight and dance, with instuments such as berinbau and batuque (a type of drum), that originated from the African slaves that were brought to Brazil. It was prohibited to practice fighting during the slavery period, so the slaves would mix fighting with music as a way to keep their African culture alive and have fun during those terrible times.
Some points of similarity between Capoeira and Luffy’s Gear 5:
1- They both wear white;
2- The importance of music;
3- Both simbolize freedom and a way to fight oppression;
4- Capoira is a dance, a way to have fun, so for Luffy he can only be on Gear 5 if he is also having fun.
*by EduMelo