Watase is a muscular man with a relatively short, stocky build, putting all his weight behind his attacks. He has short dark hair, slicked back with a widow's peak, as well as a goatee.
Watase's tattoo covers his biceps, upper chest, and stretches from his neck to his lower back. It depicts the Asura King on his back, a vajra on his left arm, and a cakraratna wheel on his right arm. This is a portrayal of a battle between Taishakuten and the Asura King, in which Taishakuten uses the vajra and the cakraratna to attack the Asura King.
His attire consists of an offwhite pinstriped double-breasted suit worn over a black dress shirt, checkered tie, and white oxfords. Additionally, he wears a Watase Family crest pin on his lapel and is often seen in sunglasses.
A fierce "man's man" with no interest in money, schemes, or fussing over the finer details, Watase loves fighting more than anything else and is considered the Omi Alliance's most militant. He possesses an overwhelming presence and a great deal of charisma, described as running the Watase Family, the largest organization in the Omi's ranks, on charm alone. Though he often lets his emotions get the better of him, he is capable of being remarkably observant and well-informed, and prefers to remain a spectator until push comes to shove.
Watase aspires to be the strongest in Japan and take control of the whole country in an all-out war against the Tojo Clan as the Omi's eighth chairman, surpassing the might of Ryuji Goda. However, he does not care to do so without going up against the "strongest of the strong," and views Kazuma Kiryu as the only worthy opponent to lead the Tojo Clan during the conflict. His grand visions of war indicate to Kiryu that, in Watase's eyes, "being a yakuza is a way to die."
As an old-school yakuza, Watase only respects power and authority, and appears to have a strong sense of loyalty and an understanding of the responsibilities of his position. He holds a high opinion of Kiryu due to his legendary status, to the point he would begrudgingly accept the long-neutral Yomei Alliance becoming affiliated with the Tojo Clan if Kiryu oversaw the proceedings.
Watase was loyal to Tsubasa Kurosawa long before and after he took the position of seventh chairman, to the point of agreeing to swear an oath of brotherhood with Minoru Aoyama on Kurosawa's orders despite his disgust at Aoyama's low rank in comparison to himself. Due to Kurosawa's worsening condition, he decided he would start doing things his own way.
Confident he was the only viable candidate, he intended to launch a full-scale war against the Tojo Clan when the time came for him to take over as eighth chairman. However, he found himself unimpressed with the Tojo in its current state and considered it too pathetic under Daigo Dojima's leadership to be worth defeating. He began trying to track Kazuma Kiryu's whereabouts down after his sudden disappearance from Okinawa six months prior to the events of Yakuza 5 in the hopes of convincing him to come back to the Tojo Clan and return it to its former glory.
Yakuza 5: 2012
On a tip from Aoyama, Watase arrives in Nagasugai, Fukuoka, where he first encounters Kiryu at the hostess club Olivier. Recognizing Kiryu near-immediately due to his notoriety among yakuza, Watase treats Kiryu with respect, addressing him as "Kiryu-han." Kiryu, however, believes that he is the one responsible for Daigo Dojima's disappearance, and reacts with hostility.
Watase reveals that he learned of both Kiryu's whereabouts and Daigo's disappearance from Minoru Aoyama, his sworn brother and assistant to Daigo. He also reveals his true goals; to become the eighth chairman of Omi Alliance and stage a war with Tojo Clan - but only if the Tojo Clan is a strong adversary. As it stands, he refuses to fight them in their weakened state. He asks Kiryu to return to the Tojo Clan, viewing Kiryu as the true opponent he must face as opposed to Daigo.
Yakuza: Like a Dragon: 2000-2019
Watase continues to serve as captain of the Omi Alliance under its eighth chairman, but is sent to prison in 2017. In his absence, he appoints Masumi Arakawa as acting captain of the Omi Alliance. He appears to have been discharged from prison by the start of 2019.
After announcing the disbandment of the Omi Alliance, he established a legitimate security company based in Osaka alongside Daigo and other former high ranked Tojo clan officers.
- Watase's tattoo was originally intended to depict a Nio guardian statue.
- In a poll conducted in 2013, Watase was voted the eighth most popular character in the Yakuza series, coming in at 105,898 votes.
- In a poll conducted in 2018, Watase was voted the eighteenth most requested character for Ryu ga Gotoku Online, coming in at 28,678 votes.