Yumi is decorated to resemble what its audience might imagine ninja headquarters to look like, including hanging lanterns and paper sliding doors. The waiters periodically choreograph martial arts moves, sneak around, and exhibit other stereotypical ninja-associated behavior. (This may attract a number of would-be actors, as Jared and his friend Justin are shown to be.)
Japanese food choices are on its menu. However, the alcoholic beverages seem to merely be given ninja-esque sounding names, such as "Ninja Ale" and "Virgin Killing Colada." The latter comes with a free rubber throwing star.
Yumi benefits from one perk that most of the other staff (save Justin) don't know about: Brown Widow watches over the restaurant. He reveals his superhero identity when he confronts Rocco and Brock Samson, who barge in believing the place to be an actual ninja headquarters where Hank and Sirena are being held hostage.