Chapter 809 is titled "Master Nekomamushi".
Color Spread: Luffy, Robin, Franky, and Brook are sitting down with some cats and are all wearing sunglasses. Brook and Robin are smoking, while Luffy sucks on a lolipop and Franky chugs some "MECHA COLA". Franky, Robin and Luffy all have extra tattoos, and Brook, whose cigarette fumes are leaking out of his empty eye sockets, is about to play a record of "Binks' Sake". The background of the illustration reads "SEA FREAK". In front of Robin is a cigarette box with the words "KILLED BY SMOKE" on it.
Inuarashi explains the antagonistic relationship between him and Nekomamushi, the master of the Whale Forest. Back in the past, Inuarashi and the Musketeer Squad arrived to battle Jack, with Inuarashi succeeding in holding back one of Jack's attacks, but were forced to retreat due to the sun setting. Nekomamushi and the Guardians then arrived and Nekomamushi flipped Jack over, forcing the pirate to revert to his human form.
Luffy questions the usage of Caesar's gas weapon as Inuarashi looks at Brook and drools. Brook sees this and gets scared, but Inuarashi promises to wait until the pirate recovers from his injuries, though Brook is not fine with that either. Robin notes that Caesar must produce the weapons, Doflamingo distributes them, and Kaido receives them. However, Inuarashi changes the subject when he notices Luffy's straw hat, saying that he and Nekomamushi once sailed the seas and met Shanks. Luffy is excited to hear this, but to his shock Inuarashi is asleep. Wanda explains that Inuarashi rules the Mokomo Dukedom during the day while Nekomamushi rules during the night due to the antagonistic relationship between the two. Usopp asks why their relationship is like that, but Wanda does not know, and says that the two used to be inseparable friends. Relations became so unbearable that the two split their working hours; Inuarashi ruled from 6:00 in the morning to 6:00 at night, and Nekomamushi would take over until 6:00 in the morning came again. The Straw Hats notice that Miyagi and Tristan are asleep as well, and Shishilian says that all the minks in the fort are affected by this schedule, with the minks in the Whale Forest taking over everything, including combat duties.
As Shishilian falls asleep, he remembers Jack's invasion 17 days ago. As Jack and the Gifters rampaged, the Musketeer Squad arrived and began a counterattack. One of the Gifters turned his hand into a wolf's head and attacked Wanda, but was stopped by Shishilian, who arrived with the other Inuarashi Musketeers. The Musketeers were then told to fall back as Inuarashi rode in, ordering the Beasts Pirates to stop their attack at once. To the minks' shock, Inuarashi threw down his sword and openly told Jack that the pirate could search the island for Raizo if he ceased attacking. However, Jack refused and swung his trunk at the duke, causing the minks to gasp in fear. However, Inuarashi easily stopped Jack's attack, and the Beasts Pirates were shocked that the minks were putting up a fight, but were confident in their captain because he was worth 1 billion. Jack told Inuarashi that he would only stop attacking once Raizo stood before him and that he loved destruction.
Giving up on reasoning with the pirate, Inuarashi picked up his sword as the Eruption Rain started, which threw the Gifters into chaos. Inuarashi and the Musketeers then attacked the Beasts Pirates, but the battle was short-lived as the clock struck 6:00 and Nekomamushi's roar rang out. Inuarashi then ordered the Musketeers to retreat, and warned Jack that the pirate was not the only obstinate person around. Nekomamushi and the Guardians then rushed forward, with their leader promising to show no mercy to intruders. Nekomamushi flew toward Jack, grabbed him by the trunk, and proceeded to flip him onto his back. Nekomamushi told Jack that if a samurai did step foot on Zou, he would already be digesting in his stomach as Jack reverted to his human form and prepared a counterattack.
- It is revealed that Caesar made weapons for Doflamingo, who in turn distributed them to Kaido.
- Duke Inuarashi is the official ruler of the Mokomo Dukedom, whereas Master Nekomamushi is the guardian of the Whale Forest and ostensibly has the same amount of power as Inuarashi.
- Duke Inuarashi and Master Nekomamushi hate each other, but they used to be friends.
- When the dukes are no longer friends, Inuarashi rules the dukedom during the day "with the sun" from 6:00 am to 6:00 pm while Nekomamushi rules during the night "with the moon" from 6:00 pm to 6:00 am. This affects the warriors and citizens of the forest and town as well.
- Inuarashi personally knows Shanks.
- The flashback of Jack's attack on Zou continues.
- Jack has a bounty of 1 billion, which is the first ten-figure bounty revealed in the series.
- The Musketeer Squad and the Guardians are shown.
- Master Nekomamushi is introduced.