Gommu was born in Republic City to two immigrant non-benders. He was raised in an orphanage until he was fifteen, when he lied about his age to join the United Forces as a telegraph operator. Working on ships as they traveled the world, Gommu grew to love the nomadic lifestyle.
When the United Forces began replacing telegraphs with radios, Gommu found himself unemployed. Unsatisfied with the stationary life, he became attracted to the nomadic vagabond culture. Eventually, he gave up his residence altogether and took to roaming the city looking for work and helping out his fellow citizens. He eventually procured a fine bush in Republic City Park and made that plant his new home.
Gommu encountered AvatarKorra when she visited the park in search of food. While she was using her firebending to fry some fish she had caught in the pond, the vagabond emerged from his bush and asked if he could have one of the three "tasty-smelling fishies" Korra had caught. She granted his request and, trying to make conversation during their awkward meal, learned that the man was proud to be living in the bush from which he emerged and that there were many more vagabonds like him in the city. This confused her, as she thought that everyone in the city was "living it up", a statement met with a laugh from Gommu. After telling her that she had a lot to learn, he formally welcomed her to Republic City.
Their conversation was cut short when a guard came running toward them, yelling that they could not fish in the pond. Hopping to his feet, Gommu warned Korra that she had better "skedaddle", and promptly dove for cover in his bush. After Korra rode away on Naga, he emerged from his bush once again, waving goodbye to his newly-befriended newcomer.
With the Equalists having taken over Republic City, Korra and her friends went into hiding with Gommu, who resided underground in a shelter where benders and non-benders lived in harmony. The vagabond provided Team Avatar with food "from the best dumpsters the city has to offer", much to Asami's disgust.
Later, after GeneralIroh joined the group, Team Avatar planned to send a telegraph to Commander Bumi, asking for assistance. Gommu, being able to operate a telegraph, helped the group, and sent the message. However, the telegraph was intercepted by Hiroshi Sato. Gommu was upset when Team Avatar split up to fight the Equalists, proclaiming, "Good fortune and success to you, valiant heroes."