All of them are criminals residing in Good Luck Alley, one of San Fransokyo's most dangerous places. They engage in illegal activities such as Bot-Fights, in which they also watch their boss win battles with Little Yama.
Powers and Abilities
None of them are known to have special abilities.
Taser Rods: They are commonly seen using taser rods to subdue their enemies without using lethal force.
Motorbikes: Some of them used motorbikes once to chase Hiro throughout Good Luck Alley, although he managed to get away.
One day, Hiro Hamada challenged Yama to a bot-fight and defeated him after having tricked him to bet all of his money.
Due to this, Yama orders his thugs to "teach him a lesson", and were about to beat Hiro up until Hiro's brother came to his rescue, escaping in a scooter. Yama and the henchmen followed them, but soon everyone, including Hiro and Tadashi, were arrested.
When they were released some weeks after, they contoured their criminal lives in Good Luck Alley by Yama's side, where a few other thugs joined them, strengthening their numbers.
"Muirahara Woods" is by far the only episode where one of Yama's thugs appears, but Yama himself doesn't.