Ventus, also known as Ven, is one of the main protagonists in Kingdom Hearts Birth by Sleep. He was a Keyblade wielder before Sora ever became one, and was apprenticed to both Xehanort and Eraqus. He is the youngest of the trio formed by himself, Terra and Aqua.
Ventus's heart is severely damaged by the creation of his dark counterpart, Vanitas, and then again when the χ-blade forged from their hearts is destroyed. Both times, Sora's heart reaches out to mend Ventus's heart, and by the end of Kingdom Hearts Birth by Sleep, Ventus's heart has gone to sleep within Sora so that it can recover until it is fully healed and ready to rejoin his body, which lies comatose but safe within the Chamber of Waking.
Ventus is later woken from his slumber and returns to training with Terra and Aqua in the Land of Departure, as well as being reunited with his Chirithy.
Ventus was chosen by the Master of Masters to become a Dandelion and one of the five members to be a replacement Union leader. Once the Keyblade War is over, he then meets the other members at the Keyblade Graveyard.
Noting Ephemer and Skuld's close friendship, Ventus admits that he is envious of them because he has always been alone. Skuld and Ephemer assure Ventus that they consider him a friend. When the fourth Union leader, Brain, arrives, he asks them if the rules Ava provided them were absolute, which Skuld confirms, prompting Ventus and Brain to comment that Skuld shares Ava's diligence. When Ventus and Brain voice their discomfort with lying to their comrades about the Keyblade War, Ephemer states that no one else should have to carry the burden of the past, a sentiment Ventus and the others accept.
After the final Union leader, Lauriam, arrives, the Union leaders go to Daybreak Town and enter the Foretellers' Chamber. When Skuld proposes that they begin choosing which Union each of them will lead, Ephemer recommends that they maintain the Union χ in order to prevent the conflicts of the past world, with the other Union leaders agreeing to reconstitute the old system later as stated in the rules. Brain suggests that, while the Dandelions are reliving the events of the past, they collect the necessary ingredients to create new Spirits and sends Ventus, Ephemer, and Skuld to collect the ingredients while he and Lauriam stay behind to make the necessary preparations.
When the time comes to discuss the matter of the Shift Pride, Ephemer calls a meeting between the Union Leaders. Lauriam does not attend, with Brain explaining that, whatever the agenda is, Lauriam asked to side with Ephemer. Proceeding, the group discusses the nature of the Shift Pride. Having not initially understood what the Shift Pride was, Ventus rejects the notion, not wanting to see wielders fighting one another again, to which Skuld concurs. Brain affirms that it is a law, and thus they should follow through with it, also believing that a little recreational contest would be fun for everyone. When Ephemer admits that he wants to follow the rules, the vote is in favor of the Shift Pride. Ephemer then explains that he intends on having wielders compete against the data versions of their comrades to avoid a clashing of hearts, admitting that Lauriam had given him the idea. The group wonders about who Lauriam could be looking for, but on Brain's suggestion, they decide to wait for Lauriam to come to them rather than pry.
Lauriam soon joins them, but rather than wanting to discuss the Shift Pride, he asks Skuld what she knew of his sister, Strelitzia, explaining that Strelitzia had been looking for someone and was last seen entering the same building Skuld had just prior to the Keyblade War. Although Skuld doesn't offer much insight, Lauriam accepts this and worries that Strelitzia may have ended up fighting in the Keyblade War after all. Brain notes that the entire situation seems odd, and after reviewing the information Ephemer is reminded of Player, then leaving with Lauriam to reconnect with Player.
Left alone with Brain and Skuld, Ventus periodically looks to Brain as he reads from the copy of the Book of Prophecies. When Brain takes notice, he asks him what's wrong, with him noting how Brain seems to be constantly reading the Book of Prophecies and asking if he'd been researching something. Brain reveals that he has a goal, and that at present, they are still following a destructive destiny, one which he intends to overwrite. Mentioning that, even if they overwrite the Keyblade War, nothing would change, Brain resolves to become a virus to overwrite that destiny, then leaving to enter the control room.
Four years before Aqua and Terra take their Mark of Mastery exam, Ventus served as an apprentice to Master Xehanort, as part of the elderly Keyblade Master's plans to forge the legendary χ-blade. However, Ventus proved to be a poor candidate, and when he refused to use his darkness to fight several Neoshadow Heartless in the Keyblade Graveyard, Master Xehanort finally lost patience with him and used his own Keyblade to unlock and extract the darkness from Ventus's heart, using it to form a being of pure darkness who was then named "Vanitas" by Master Xehanort.
Unfortunately, the process left Ventus in a comatose state, with his broken heart of pure light slowly fading out. Master Xehanort, disguised in a black coat, then took Ventus to the Destiny Islands to allow him to live out his last days peacefully. Ventus was sent to the Dive to the Heart, where he came in contact with the heart of a newborn Sora. After a brief discussion, Ventus's heart connected with Sora's, halting its deterioration and allowing Ven to stay alive until he someday becomes strong enough to repair the damage by himself. Ventus then summoned a Keyblade and shot a ray of light into the sky above, much to Master Xehanort's surprise. Xehanort decided that Ventus could still be of use in his master plan, but with Ventus still too weak in comparison to Vanitas, the two boys could not be trained under him since Vanitas had a naturally strong impulse to destroy Ventus.
To prevent this, Xehanort brought Ventus to Land of Departure, where he could train as an apprentice to Master Eraqus. Terra and Aqua met Ventus with open arms. However, when Terra asked Ventus about his past, he screamed out in agony, eventually falling unconscious. Eraqus revealed that this was because Ventus had lost his memories. Afterwards, he remained asleep for some time. As he slept, Aqua kept watch over him, to keep him safe. Some time later, Ventus woke up. Overjoyed, Aqua quickly alerted Eraqus and a worried Terra about Ventus's recovery.
It was then that his heart began to heal and he started to form strong bonds of friendship with Terra and Aqua. During a training session, Ventus loses humiliatingly, but Terra and Aqua reassure Ventus that he was getting stronger. As time went on, Terra and Ventus grew close, forming a strong bond. Terra even went so far as to give Ventus his wooden training Keyblade and recite a mock Bequeathing ceremony. Together, the three of them shared the same dream: to become Keyblade Masters.
And he reprised by Jesse McCartney in the English dub and Koki Uchiyama in the Japanese dub.