Personality

Ino is somewhat superficial, constantly thinking about boys and hoping to diet to lose weight in order to be more attractive to them. She sometimes suggests that Choji should lose weight, but in the filler arcs, suggests that his fat is essential for his techniques. She is attracted to Sasuke, but her reasons for that attraction, apart from Sasuke being a popular student and the best in his class, are unknown.
In her team, Ino tends to boss the others around. Shikamaru, despite thinking of most girls, especially her, as "troublesome," typically offers no resistance, being unwilling to deal with how she reacts if she is unable to have her way. Asuma recognizes the control she has over the others, and while dying, tells her to look after Choji and Shikamaru and ensure that they do not get into trouble.

Chunin Exams

In the anime, Ino plays a small role in Episode 3, being upset when she does not get onto Sasuke's team while Sakura does, and being dismayed to be on the same team as Shikamaru and Choji.
Ino later reappears in the Chunin Exam. She uses her Mind into Body technique to enter Sakura's mind and memorize all her test answers, then sends her mind into Choji and Shikamaru's minds to give them the answers. In the Forest of Death, she helps Sakura and Lee fight off the Sound Genin until Sasuke, his Cursed Seal having awoken, forces the Sound Genin to retreat.
Ino's first match in the Chunin Exams is against Sakura. The two do not battle seriously at first, until Sakura, unwilling to have Ino pity her, denounces her. Ino and Sakura battle seriously afterward and use up most of their energy in the process. Ino then attempts to enter Sakura's mind after cutting her hair and sending chakra into it to immobilize her. She succeeds, but is expelled by Inner Sakura. Low on chakra, Ino and Sakura charge each other for one last attack, and knock each other out, resulting in both of them being eliminated. When they regain consciousness, they start becoming friends again, but still maintain their rivalry over Sasuke.
Ino accompanies Sakura to visit Sasuke in the month between the preliminaries and the finals, but finds that he is gone. She goes to the finals with Sakura, and notes that Sakura's team is extraordinary after seeing Naruto defeat Neji. When the invasion starts, she is rendered unconscious by Kabuto's genjutsu; Sakura briefly considers waking her to help pursue Sasuke, but Kakashi tells her that a group of more than four people (her, Naruto, Shikamaru and Pakkun) would not move effectively.

Filler Arcs

In the filler arcs, Ino accompanies Naruto, Shino and Anko to the Land of the Sea, and helps defeat Misumi Tsurugi by possessing him and tying his arms to pillars, leaving him trapped in a collapsing room. Ino then uses Mind-Body Break Technique on Yoroi as he attempts to attack Shino, allowing Shino to punch Yoroi away. When Yoroi attempts to attack Ino, Shino sends his bugs after him, defeating him.
She later appears in a mission with Naruto, in which she tries to replace a princess who has grown overweight in an attempt to woo her suitor. Ino is barely able to stand the man, but the mission succeeds after Naruto, while interfering, accidentally exposes the real princess.
In the Konoha 11 arc, Ino and Sakura are sent to examine a corpse that is believed to be that of Genno. Ino hesitates, but eventually enters the room, and concludes from the condition of the hands that the corpse was not a ninja or a carpenter, and that Genno is still alive. After the group finds Genno, she attempts to possess him when he tries to make his escape on a summoned bird; while he lets go of the bird, Ino is unable to maintain the technique, as she notes that he has been suffering terrible pain the entire time. Genno dies shortly after his plans are foiled, possibly from what had caused that pain. In the final filler arc, Ino's attempt at possessing Kyaku fails, leaving her at risk, but Kyaku is defeated by Shikamaru and Temari's combined efforts. Feeling guilty that she did not contribute much to the mission, she asks Sakura to ask Tsunade to add her as a second apprentice. Sakura agrees, but adds that she will be Ino's senior apprentice (leading to yet another fight).

Part II

In Part II, Ino knows medical jutsu, but her skills have not been shown as often as Sakura's. She attempts to save Asuma with her medical jutsu, but his wounds are too severe to be healed.
[edit]

Hidan and Kakuzu Arc

It is also shown that she is starting to become attracted to Sai. While he refers to her as a "pretty lady," he does so while trying to give her a pet name that is the opposite of how she appears, indicating that she may possibly, in fact, be ugly to him.
Later, Ino and Choji arrive as backup for Shikamaru and Asuma in their fight with Akatsuki members Hidan and Kakuzu. As the Akatsuki pair flees due to their arrival, Ino tries to use medical ninjutsu to heal Asuma's injuries, though she knows that there's nothing she can do to save her sensei. Asuma, also knowing that he won't make it, gives some parting words to his team. To Ino, Asuma says that her spirit is strong and that she is a helpful child, so she should take care of Choji and Shikamaru. Asuma also tells Ino not to lose to Sakura in ninjutsu or in love, to which Ino agrees. After smoking one last cigarette, Asuma dies, leaving Ino, Choji, Shikamaru to set out in an attempt to avenge him. By using her Mind Body Switch Technique on a hawk, Ino is able to find the Akatsuki duo. During Team 10's fight with Hidan and Kakuzu, Ino plays the role of an observer, her Mind Body Switch Technique too much of a risk to use in battle. She heals Naruto after he defeats Kakuzu.

Abilities

Ino is considered one of the more talented kunoichi in the academy, and is fairly skilled in most ninja arts. She primarily uses mind-affecting jutsu, such as the Mind-Body Switch Technique, a jutsu used for reconnaissance, which allows her to possess someone and control that person's actions for about two to three minutes. However, her body feels any pain that the target feels while possessed, and she will die if the target dies. Missing results in her being unconscious for several minutes while her mind returns to her body, leaving her extremely vulnerable.