The Ambition of Oda Nobuna

Yoshiharu Sagara finds himself in the Sengoku era and his life saved by the sacrifice of Hideyoshi Toyotomi. When he saves a teenage girl from enemy soldiers, he is surprised to discover that the girl is a female Nobunaga Oda named Nobuna Oda, the Daimyo of Owari. Furthermore, he also discovers some of the historical warlords of this era are female as well. As a reward of saving her life, Nobuna makes Yoshiharu her retainer but she, including her other servants Katsuie Shibata, Nagahide Niwa and Inuchiyo Maeda, are skeptical of his claims that he is from the future. Nevertheless, he vows to take over Hideyoshi's role in helping Nobuna. Meanwhile, the Daimyo of Mino, Dōsan Saitō, calls for a meeting with Nobuna over an alliance. Dōsan's servant Mitsuhide Akechi attempts an ambush on the Oda delegation but her plans are thwarted by Yoshiharu who convinces Nobuna to have her troops prepare their rifles. During the meeting, Nobuna reveals to Dōsan of her dreams for Japan and Yoshiharu reveals to him how will history view him in the future if he accept the alliance. Impressed by Yoshiharu's speech, he agrees to ally with the Oda clan by making Nobuna his heir.

Yoshiharu gets into trouble after he hits Nobukatsu Oda, Nobuna's younger brother after the latter insulted his sister. Nobukatsu demands his head as punishment but Nobuna can save Yoshiharu's life if she makes him a general but he must first prove his worth by assigning him to gather 8,000 koku of rice in a week. Using his marketing strategy of buying low and selling high, Yoshiharu manages to gather enough gold to buy the rice four times more than he was tasked in a week thanks to his ninja servant Goemon Hachisuka and Inuchiyo's help. However, Nobukatsu launches a rebellion after being convinced by his advisers that his sister is not fit to rule the clan. But Nobukatsu's rebellion is quickly and peacefully stopped after Nobuna's forces surround Nobukatsu's castle where Yoshiharu and the soldiers shout rally cries that scares Nobukatsu into submission. Nobuna attempts to kill Nobukatsu to set an example to others but Yoshiharu forces her to stop as he knows she still loves her brother and doing so will make her ruthless just like Nobunaga. Convinced, she forgives her brother who in gratitude, swears to never to rebel again and changes his name to Nobusumi Tsuda. Nobuna thanks Yoshiharu for what he did and makes him swear his loyalty to her.

Dōsan's son Yoshitatsu launches a coup d'état against his father for allying with Nobuna. Despite Nobuna's wish to send reinforcements, everyone knows they cannot do it for it will allow the Daimyo of Suruga, Yoshimoto Imagawa, the opportunity to invade Owari. Meanwhile, the Daimyo of Oumi, Nagamasa Asai meets with Nobuna to propose an alliance between their clans which will allow her armies to help Dōsan while his armies protect her borders against the Imagawa clan in exchange she marries him. However, Yoshiharu and the others loathes Nagamasa as he threatens to ally with the Imagawas if Nobuna refuses and he does not care about her feelings and is only interested with the benefits he gains as her husband. Yoshiharu, Katsuie, Nagahide and Inuchiyo convinces Nobuna to decline his offer. Not soon after that, Mitsuhide arrives with Dōsan's daughter Kichō, who Dōsan's entrusts her well being and his dreams to Nobuna as he prepares for a last stand near a river. Katsuie is forced to knockout Nobuna to prevent her from doing anything rash. Not wishing to see Nobuna sad over Dōsan's death, Yoshiharu, Goemon and a small group rescues Dōsan and his men as they escape to Owari from Yoshitatsu's forces through the river. Despite Yoshitatsu attempts to kill them, they are force to retreat when the Oda army saves Yoshiharu's group. As Nobuna berates Yoshiharu for his foolishness, everyone is soon informed that Yoshimoto and her army have invaded into Owari.

Nobuna fires Yoshiharu, blaming his actions that gave the Imagawas the chance to invade Owari. Yoshiharu becomes depress but Dōsan reveals to him the reason Nobuna fired him was because the people she cared had die and doesn't want the same fate happening to him. Encouraged by Dōsan to continue helping Nobuna, Yoshiharu heads out with his men, Goemon, Inuchiyo, Nobusumi and his female bodyguards to find Okehazama, where Yoshimoto's camp is located and where Nobunaga defeated the Imagawas in his timeline. After finding the camp, Nobusumi and his bodyguards distract Yoshimoto's men so that Yoshiharu can give the camp's location to his sister. However, Yoshiharu's entourage are confronted by ninjas lead by Hanzō Hattori. Despite the others holding them off, Hanzō captures Yoshiharu but the latter manages to convinces Hanzō to let him go as if Yoshimoto's is defeated, his master, Motoyasu Matsudaira, will no longer be a vassal of the Imagawa clan. Finally receiving Yoshiharu's intel, Nobuna and her army leads a surprise attack on Yoshimoto's camp. Due to rain and her men drunk due to Nobusumi, Yoshimoto's men are caught off guard and easily defeated by the Oda army. Katsuie is about to kill Yoshimoto but Yoshiharu stops her by groping her breasts as Yoshimoto is a cute girl. After Yoshiharu charms her, Yoshimoto agrees to surrender, ending the war. Nobuna thanks Yoshiharu for his help but also punishes him on what he did with Katsuie and Yoshimoto.

After forming an alliance with Motoyasu, the Oda army begin their attack to reclaim Mino from Yoshitatsu. However, their attempts are repeatedly thwarted by Hanbē Takenaka, an Onmyōji and Mino's secret tactician. Dōsan's tells Yoshiharu, Mitsuhide, Goemon and Inuchiyo where they can find Hanbē and convince Hanbē to join the Oda army. Upon reaching Hanbē's home, they soon discover Nagamasa is there as well to convince Hanbē to join his side, hoping to use this to make Nobuna marry him. Yoshiharu and Nagamasa are greeted by a man claiming to be Hanbē who has them take a test that will convince him who's side he will join. However, the test is a ruse as the man claiming to be Hanbē is Hanbē's Shikigami familiar and the real Hanbē is a shy, young girl who hates violence. Meanwhile, Hanbē's uncle is arrested by Yoshitatsu as he is suspicious on Hanbē refusal to come and swear loyalty in front of him and using battle strategies with the least amount of bloodshed and orders Hanbē to come to Inabayama castle or her uncle will be killed. Having a plan to save her uncle, Yoshiharu and Nagamasa accompany Hanbē to meet Yoshitatsu while Mitsuhide, Goemon and Inuchiyo rescue her uncle. Despite her pleas she will never betray him, Yoshitatsu refuses to believe Hanbē as he sees her strategies of sparing her enemies lives as treason. As Yoshiharu calls out Yoshitatsu for treating Hanbē horribly, his allies manage to rescue Hanbē's uncle and attempt to escape. However, Yoshitatsu has taken Hanbē hostage which the frighten girl summons her familiars which defeat Yoshitatsu and his men. After finally escaping, Hanbē swears her loyalty to Yoshiharu after being touched by his kindness and his loyalty to achieve Nobuna's dream.

Nobuna plans to build a castle at Sunomata near Nagara River which would allow her to conquer Mino. Despite Yoshiharu wishes to lead the task, Nobuna refuses and assign it to her other Generals as not to be seen playing favorites. However, Sunomata is near Inabayama castle and their attempts to build are repelled by Yoshitatsu's forces. Reluctantly giving the task to Yoshiharu, Nobuna and Katsuie leads most of the Oda army to Kisogawa to divert Yoshitatsu's attention while Yoshiharu, Hanbē, Mitsuhide, Goemon and Inuchiyo leads a small force to secretly a build a castle at Sunomata during the night. Meanwhile, Yoshitatsu's Generals Inaba and Ujiie are starting to question their lord's leadership after Hanbē's defection. Yoshitatsu sends Inaba and Ujiie to lure Nobuna's forces at an abandoned gold mine in a valley. Unknown to everyone, Yoshitatsu real plan is to kill everyone there by trapping them in the valley after setting it on fire. But much to Yoshitatsu rage, he learns a castle has been built at Sunomata the following morning and sends his army to destroy them. As Yoshiharu and the others hold off the Mino army until reinforcements arrive, Nobuna manages to escape the valley and convinces Inaba and Ujiie to defect to her side as their combined forces help the defenders of Sunomata and defeat the Mino army. Nagamasa tries to use the battle to launch a surprise attack on both sides only to encounter Nagahide's army who expected this. With Yoshitatsu captured and Mino now under her rule, Nobuna decides on Yoshitatsu fate. Much to Dōsan's anger, Nobuna spares Yoshitatsu's life. As he gets drunk in anger, Yoshiharu makes Dōsan understand Nobuna's reasoning and has him see the newly built town of Gifu and Gifu Castle, which Nobuna built in his honor. (Gifu means stepfather.)