|Portrayed by:||Chao-Li Chi|
|First appearance:||Night of the Ninja|
|Last appearance:||Day of the Samurai|
|Appears in:||2 Episodes|
Yoru Sensei ran a martial arts academy in Japan, and was a teacher of the young Bruce Wayne.
As a young man, Bruce enrolled himself in Yoru's dojo for an extended period to learning numerous martial arts. He rose to become one of the dojo's best students. The only other student able to consistently defeat him was Kyodai Ken. Bruce, realizing he couldn't operate like this as Batman in the future, obsessed over these defeats, turning to extreme methods to get better. Yoru was concerned that Bruce was not practicing out of a desire to sharpen his skills, but out of fanaticism, and counseled him to learn from his mistakes and turn them to his advantage, pointing out that sometimes losing can be more profitable than winning. Bruce still believed that one slip would be too many, and Yoru likely did not know the true purpose of his training. However, Yoru's lessons did have a later effect on a full-grown Bruce, who as a more mature individual did realize that as Batman there would be some cases when the enemy does have the upper hand, but it would not always mean doom. When Kyodai was caught trying to steal and ancient samurai sword, Yoru expelled him from the dojo.
Several years later, Yoru's star pupil, Kairi Tanaga, was kidnapped by Kyodai, in exchange for a precious secret. Yoru summoned Bruce, asking for his "help" in contacting Batman, possibly having guessed his student's secret. Yoru revealed that he was the last living direct descendant of an ancient sensei who had invented an amazingly deadly fighting art, "Kiba no Houkou", The Way of the Fang. The scroll manual for the art had been passed down in his family for generations, but Yoru never read it, afraid of what he might do with such knowledge. Kyodai demanded the scroll in return for Kairi's safe return. Through Bruce, Yoru delivered the scroll's location, honoring his code of Bushido to remain truthful.
Bruce fought defeat Kyodai in a fight on the side of a volcanic mountain, in which the latter was likely killed in an explosion of lava.
Before leaving Japan, Bruce and Yoru discussed Batman. Bruce said, somewhat shamefacedly, that Batman was as much a ninja as Kyodai, a man who relied on darkness and fear to terrorize his enemies. Yoru replied, not so: Batman had showcased all the traditional values of the samurai: resolve, honor, and mercy toward his adversary.
In later years, Kairi became a respected sensei in her own right, opening an exclusive, secret dojo behind her fishmonger's stall in Gotham City.