|Anime||Naruto Shippūden Episode #156|
|Novel||Shikamaru Hiden: A Cloud Drifting in Silent Darkness|
|Movie||Naruto the Movie: Blood Prison|
|OVA||Chūnin Exam on Fire! Naruto vs. Konohamaru!|
|Appears in||Anime, Manga, Novel, Movie|
Omoi is a very cautious person and likes to think things through before acting, and as a result, gets lost in his thoughts quite often. He is more level-headed than his team-mate Karui, but has a habit of exaggerating the end result of minor things (like when Karui threw a rock at him and he believed it would cause an avalanche and destroy Konoha) and likes to make fun of Karui's hot-headed personality with painful results. He also has respect for people who stand by their word, even if they are the enemy. He is a very intelligent ninja. It has also been said by his team-mate, Karui, that he is rather pessimistic when he expresses his concern for Killer B. Nevertheless, he is capable of becoming deadly serious and exhibits great conviction when the situation demands it; having expressed disgust when he saw that Akatsuki was making Sai fight his brother and stepped in to prevent that from happening.
== Appearance ==Sakura]], and Sai talking about Sasuke, B's captor. They demand all information they have on Sasuke, leading to a brief scuffle between the two groups. Omoi informs them of Sasuke's actions and promises to take vengeance against him which, if Konoha and Kumo are to be allies, they should help him with by providing information that can be used to kill Sasuke. Naruto assures them that there may be time to save B and offers to tell them everything they want to know. When it comes time do to so, however, Naruto can't bring himself to sell out Sasuke. He offers to let Karui beat him up, which she gladly does. Omoi watches for a time but then encourages her to stop, commenting that Naruto didn't seem to be the type of guy to rat out a friend - despite them being an enemy - which Omoi respected.
After reuniting wiKankuro attack Shin.png|thumb|left|The Ambush Squads battle.]] Because Deidara is among the enemy's ranks, the division needs a way to deactivate his earth-based explosive clay. Omoi volunteers to to try neutralising the clay with his lightning-infused sword. After he and Kankurō engage Shin who was being manipulated by Sasori and struggles to hit a moving target, Omoi is finally able to pierce Deidara after they are ruthlessly attacked by enraged Sai and is trapped in one of Kankurō's Black Ant puppets, deactivating his bombs.
Omoi, Sai, and Zaji are sent out to find other Akatsuki cells. They come across and attack a group consisting of Haku, Zabuza, Gari, and Pakura, but Sai's aerial attack of explosive tags fail and Haku attacks them using his Demonic Mirroring Ice Crystals. Before they can be killed the Third Division arrives to help. They later join the division protecting Kakashi while he executed his strategy.
In the anime, he, Zaji, and Sai would later join up with the Third Division and battle Fuguki Suikazan and he and Zaji would go off to aid Maki and her team to fight Gari and Pakura. When Yurui's team was set upon by Ameyuri Ringo, he and a few others were able to escape the attack. As they retreated on Nurui's orders, Omoi was adamant that they could not run forever and needed to make a stand and fight despite Nurui's disapproval. Disregarding his orders, he leaves Nurui and Kayui to confront Ameyuri head on. An intense battle with the kunoichi soon ensued and though Kayui and Nurui returned to offer assistance, they were struck down by the legendary swordswoman and her swords. In the end, Omoi was able to trap Ameyuri in a marsh and as they both sank, reinforcements arrived and were able to rescue Omoi. Ameyuri, who had taken a liking to Omoi, gave him her swords as a parting gift before being completely submerged in the marsh.
Along with the other remaining members of the Allied Shinobi Forces, Omoi made his way to the battlefield where the jinchūriki were. Meeting up with Karui, the two immediately went to B's side when they arrived, where the two proceeded to make sure that their sensei was all right. They later stood alongside the others to face their opposition.
Naruto 5: Blood Prison
- His name is a pun on two words which have the pronunciation "Omoi":
- 重い, which means "heavy", contrasting with Karui, which means "light".
- 思い, which means "thought", alluding to his thoughtful manner.
he enjiys sucking butt\
- (After being summoned by the Raikage) "What the hell does he want? Is it something big…? Or… is he gonna scold us for something? Should I have not put mayonnaise on my fries?"
- (To Karui) "You need to think things through more carefully…"
- "No time to be anxious… I won't let you force friends and family hurt one another!"