AppearanceSengoku is a roughly middle aged man with a long braided beard and a mustache. He is usually seen alongside his pet goat. He typically wears glasses and a full Marine Admiral uniform adorned with medals. The most distinctive featur e of this uniform is a life-size seagull on top of his cap, and his oversized Marine coat, which he wears like a cape.
Twenty years ago before the present storyline, while Sengoku was still an Admiral, he sported an afro and a beardless face. He also wore a less regal attire than he does in the present storyline, a simple black tank top, blue jeans, and his glasses, which is unlike a typical Admiral's f ormal suit. The only Marine related attire he wore at the time was seemingly being his Marine coat, draped over like a cape.
PersonalityHe appears to be a proud man who is loyal to the World Government and never questions orders. He is somewhat biased against pirates and seems to show displeasure towards at least one of the Shichibukai, though he notes how valuable they could be when the time comes. He also can't accept any reason for letting a criminal go — not even on the grounds of moral values. He also gets very irritated with failure, and does not tolerate it from anyone he gives orders to.
As of lately it would seem that he has gained a concern in the movements of the Straw Hat Pirates, and has followed their movements ever since leaving Water 7, though his current concern is about the upcoming war against Whitebeard, to the point that he brushed off inci dent of the attack of a Tenryuubito to the Admirals. Upon hearing Luffy's break-in of Impel Down, Sengoku was so frustrated that he almost took it out on Garp. He follows the code of Absolute Justice.
Monkey D. GarpAs Garp is considered a "Hero of the Marines", Sengoku, along with the rest of the Marines, respects him greatly. However, after discovering that Garp withheld information that the infamous Monkey D. Luffy is his grandson, Sengoku became furious with the man. With this added to the frustration caused by Luffy's repeated actions against the W orld Government, Sengoku is beginning to lose patience with Garp. Garp, on the other hand, enjoys getting on Sengoku's nerves.
Sengoku has somehow found out that Garp has adopted Portgas D. Ace, son of Pirate King Gol D. Roger, which was meant to be kept secret from the World Government. Sengoku warned Garp not to do anything foolish in terms of Ace's execution, or there will be no mercy. Sengoku also knows that the Revolutionary Dragon is Luffy's father, and by extension Garp's son. It is unknown when or how long Sengoku knew about all these, or how it would affect Garp's standing in the Marines.
ShichibukaiAs with Commodore Smoker and Admiral Kizaru, Sengoku believes that the Shichibukai are no more than pirates, and therefore, trusts them little. However, he sees them to be very useful at times of need. When these World Government allies refused to live up to their duties, such as Boa Hancock, Jinbei, and Marshall D. Teach did, Sengoku shows his frustration at them.
WhitebeardAs Sengoku was a major figure back in Gol D. Roger's time, and still is today; he is one of the few people Whitebeard respects. Currently, Sengoku is, along with the entire Marine and World Government, waging war against Whitebeard over the life of Portgas D. Ace.
Monkey D. LuffyAs time goes on, Sengoku is becoming angrier with Luffy's deeds (defeating Shichibukai Crocodile, invading Enies Lobby and defeating Rob Lucci of the CP9, defeating Shichibukai Gecko Moria, punching World Noble Saint Charloss, breaking into and out of the Great Jail Impel Down, and intruding on the war against Whitebeard).
Coupled with the fact that eac h action deals a devastating blow on the World Government, and that he's also Vice Admiral Garp's grandson, Sengoku tends to take the frustration he feels, after one of Luffy's stunts, out on Garp. Sengoku also knows that Dragon is Luffy's biological father, and considers Luffy to be the greatest threat to the world due to this heritage, exactly the same as Ace being Roger's son.
Abilities and PowersAs the commanding officer of the entire Marine force, Sengoku has absolute power over every action the Marines do. The only ones that are above him and command him are the Gorousei.
Being that he was once an Admiral, and one of the major figures that Whitebeard mentioned, it may be presumed that Sengoku has battle power on par with Aokiji, Kizaru and Akainu if not higher.
Sengoku was referred as "Strategist Sengoku the Buddha", by Whitebeard indicating Sengoku may be a brilliant strategist.
Ohara IncidentTwenty years ago before the current storyline, Sengoku used to be an Admiral. During his time as an Admiral, he received orders from the World Government to carry out a secret mission. This mission was to send a Buster Call to obliterate Ohara. With these orders Sengoku g ave the Golden Den Den Mushi for the operation to CP9 director who was to investigate the situation, Spandine. Among the five Vice Admirals Sengoku chose to lead the Buster Call were Sakazuki, Kuzan, and Jaguar D. Saul.
After the capture of Nico Olvia, Sengoku informed Saul of his role in the upcoming mission. The giant protested against this and tried to reason with Sengoku that the Oharans were merely scholars interested only in history. Sengoku however turned a deaf ear and told Saul to just follow orders. Later, Sengoku received news that Saul had freed Nico Olvia. Seeing that the Buster Call mission to Ohara was in jeopardy, Sengoku ordered his men to quickly find the two before the operation could be stopped.
After the operation was finished , Sengoku was informed by Spandine that one of the scholars of Ohara had escaped from the Buster Call attack. This little girl, Nico Robin, was deemed a threat. With that in mind, Sengoku and other high ranking officials put up a bounty of Image:Bsymbol.gif79,000,000 on her in order to help catch her.
Meeting with the ShichibukaiAfter Crocodile was defeated by Luffy and stripped of his rank as a Shichibukai, Sengoku was called in to discuss Crocodile's replacement in Mariejois, along with the various Marine officials attending there and whoever among the Shichibukai decided to show up. He had just shown up late and caught Doflamingo messing around with some of the Marine officials attending the meeting. Seeing the pirate's actions, he told him to stop immediately. With that settled, he apologized for being late, greeted everyone, and started the meeting.
As Sengoku discussed some further formalities with Doflamingo, he and everyone were suddenly surprised by Mihawk's sudden appearance in the meeting. This was quite a surprise for everyone as Mihawk was the last person they expected to come to the meeting. Sengoku and everyone else were then later surprised by the appearance of Lafitte, who had somehow sneaked in the meeting room. As Sengoku was told of the identity of this newcomer, Lafitte suggested a perfect candidate to replace Crocodile.
Sengoku was then told of Marshall D. Teach by Lafitte. Having never heard of Teach before, Sengoku told Lafitte that an unknown pirate without a reputation wouldn't be much use as a Shichibukai. Lafitte however told Sengoku that he and the rest of his crew already have a plan to make Teach famous. With that Lafitte left Sengoku and the other people attending the meeting, and told them to remember his crew's name, the Blackbeard Pirates.
After Enies LobbyAfter the big military mess that was Enies Lobby, Sengoku learned some startling information about one of the prominent players involved. Garp accidently informed Sengoku that Luffy was the Vice-Admiral's grandson. This revelation annoyed Sengoku not only because Garp withheld such information, but also because the Vice-Admiral didn't capture Luffy while he was in Water 7. Sengoku ordered Garp back to Water 7 to capture Luffy.
After Shichibukai Gecko Moria's defeat, Sengoku was seen in Mariejois with Garp and Kuma. He was very angry that Kuma was not able to capture the Straw Hats, and voiced concern about their proximity to Marine Headquarters. Garp also annoyed him a great deal.
He was later seen in Mariejois, commenting on how Luffy tends to get "into one thing after another" (mostly referring to the defeat of Crocodile, assault on Enies Lobby and defeat of CP9 and the recent victory over another of the Shichibukai, Gecko Moria ). He was greatly irritated by Luffy's attack on Tenryuubito Saint Charloss and for "taking hostage" of his father and sister. Seeing this, Admiral Kizaru offered to go to Sabaody Archipelago himself to solve the problem.
Preparing for warHe is most recently seen at Marine Headquarters, receiving the report that Vice Admiral Momonga has managed to "convince" Pirate Empress Boa Hancock of the Shichibukai to follow up the mandatory summons of the Government. Sengoku is pleased by this, and aknowledged Hancock is very strong, but is also troubled that Jinbei doesn't seem to want to cooperate with them and is prepared to lose his status, fighting the Marines, instead of Whitebeard.
Sengoku reveals the name of Ace's father.
Afterwards, an official tells him of the amount of pirates that Admiral Kizaru managed to capture at Sabaody - At least 500 pirates are to be sent to Impel Down. He is irritated by being bothered for such reason and asks to be reported about matters related only to Whitebeard. In the same manner, he brushes off the matter of the incident with Saint Roswald, saying its a matter for the Admirals. He then asks where Garp is and is irritated upon learning that he left for Impel Down a while ago. He has no real time to react to this, mainly because he then receives news that Whitebeard's main ship, the Moby Dick was on the move and that all 23 patrol ships are impossible to contact. He orders extreme caution even at Impel Down.
To Sengoku's great displeasure, he received information that Monkey D. Luffy has broken into Impel Down and, putting the dots together, Sengoku correctly deduced that Luffy's invasion within the Great Gaol itself was to rescue Portgas D. Ace from execution, in the critical time when they're supposed to be preparing for war against Whitebeard for the same reason. He was also annoyed that he was able to go and cause one incident after another; the Enies Lobby raid, punching a World Noble and now breaking into the Great Gaol. Garp, however, found it amusing that his grandson would go to such lenghts simply to rescue Ace. Sengoku angrily tells Garp that no one had attempted anything so atrocious in the history of Impel Down, since 20 years prior to current events, and was annoyed that the one who would do it was Garp's grandson. Sengoku also said to Garp that, had he not been the "Hero of the Marines", he would have held Garp personally responsible for his family's actions. Garp simply replies that the life of an old man may not atone for all of them. 
When Blackbeard stole a Marine ship with his crew and broke into Impel Down, Sengoku looked distraught at the news.
Three hours prior to Ace's execution, Sengoku told Garp that he would reveal Ace's origins to the Marines, to which Garp allowed. Sengoku then revealed to his subordinates that Ace's father is none other than Gol D. Roger, the Pirate King. He later witnesses the arrival of Whitebeard and his allies. According to Whitebeard, they have not seen each other in decades. Sengoku stated that Whitebeard ate the Gura Gura no Mi Devil Fruit and that he had the power to destroy the world. Following several attacks from both sides, Sengoku proclaims the war has begun.
When Sengoku created a plan to execute Ace before the scheduled 3:00 p.m. designation, he's interrupted when Garp sits on the execution platform, torn between family and duty. Sengoku warned him not to do anything foolish or suffer the consequences.
An Unexpected ArrivalLuffy's unceremonious self-introduction into the Battle of Marineford has Sengoku apoplectic, going so far as screaming at Garp for having his family intruding on World Government affairs again. Sengoku only gets angrier when Jimbei loudly declares his resignation from the title of Shichibukai. When asked by Kizaru if executions are in order for each and every last one of the Impel Down escapees, Sengoku agrees.
When Luffy declares that he is Ace's brother, Sengoku revealed worldwide that Luffy is not only Ace's adoptive brother, but is also Revolutionary Dragon's son, and that Luffy is the most dangerous future element, exactly as Ace is being Roger's son.