Brook
Brook was a musician, pirate and swordfighter.
Also recorded as Soul King.
In detail
Membership is recorded of Straw Hat Pirates.
Sources
Each source is named with the standing the house places on it, so the evidence can be weighed rather than taken on trust.
reference work · Reputable secondary · Wikipedia
“Brook (One Piece)”, English Wikipedia, consulted as further reading
Consult the sourcereference work · Reputable secondary · Wikidata
Wikidata, structured authority record Q4376780: Brook
Consult the source