Alan, Barry, and Cohen are three recurring characters in Tenchi Muyo! GXP. Sometimes known as "The Three Idiots", these three first appeared in the second episode of the anime, Invasion.
Background
All three of them were on board the G.P. cruiser that had picked-up Seina to transport him to the G.P. Academy. It was during the trip that they ran into Ryoko Balta's ship, where they immediately "surrendered." It turns out that the three are rabid fans of the space pirate, but were crushed when she took a liking to Seina. From that point forward, the three would be found from time-to-time, either with the G.P. or the Daluma Pirate Guild. They even served on board Seiryo's ship Unko.
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"Think of the Group! The three of us comprise one character!" |
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In the anime, they often serve strictly as comic relief. In the later episodes they're often complimenting Seriyo's own ridiculous antics. In the novels, they serve a similar function, but Alan takes a more central and disdainful role.
Alan
It seems that Alan has an unnatural influence on Barry and Cohen which allows him to convince them to follow him in badly thought out plans they normally would not go along with. Most are get-rich quick schemes or just generally selfish and they always leave them worse off than they were and cause even more problems. He constantly cheats them out of their own wages to fund failed ploys to get rich, has gotten them imprisoned and sentenced to harsh military training.
In the GXP novels, Alan convinces the trio to start a cult/fan club for Ryoko Balta, based off of the pictures they took of her when she first met Seina. They soon lose control of the club, in part because the secretary they hired was actually Widow in disguise. They also lost all of the money they made to partying and gambling, leaving them deeply in debt.
Due to their debt, they eventually return to working for the GXP, working for garnished wages to repay their debts. As no other officers want to serve with the unlucky Seina, they are assigned to crew the Kamidake. As Alan is always looking for a get rich angle or ways to meet his selfish needs, he leads the other two in an odd food-hoarding plan that almost dooms the first Kamidake.
After serving so poorly on the ship, they are reassigned for retraining on a harsh military vessel. Alan's scheming gets them caught by pirates under Kyo Komachi and later Seriyo.

Alan meets Loretta
When Seiryo leaves the Unko to duel Seina on Racepshi, he leaves it solely in the charge of Alan, Barry and Cohen. Alan, bored, leaves the ship and ultimately gets swindled into gambling away the deed to the Unko, abandoning Barry and Cohen. This is actually all a plan of Seto's to seize the ship and it is Kuis Panta who comes to claim the ship.
After a bit of lucky gambling pays off his debt, Alan runs off and marries a hostess he met on Racepshi, Loretta. In Paradise War, it is revealed that they ran up another huge debt together and then he abandoned her to cover their debt alone. Soon after, she has their daughter, Melissa. To pay off the debt they accrued, Alea Balta, Loretta's younger sister, agrees to be the Balta's proxy warrior in the proxy war to determine leadership roles in the new Pirate Nation. Alan eventually steals some supplies and money and sneaks onto Banjo Island, getting Alea to reluctantly help him. He has the stupid idea to sell his services, as the former partner of the famous Seina Yamada, to whichever guild pays him. There are standing orders to take Alan into custody on sight and Seina and Loretta basically double-team him and capture him, after a little well-deserved abuse from his abandoned ex-wife.
Barry and Cohen
Oddly, getting captured by space pirates was the best thing for Barry and Cohen. While serving in the pirate guild under the command of Kyo Komachi, Barry and Cohen are separated from Alan. Once they are away from his influence they become serious and capable workers. After being separated long enough, the two of them start to fully understand Alan's idiocy and are able to tell him directly that they will no longer follow him. The two of them decide to work off their debt honestly.
After Alan loses the deed to the Unko, Barry and Cohen tell Kuis that they can't leave the ship because of their debt, so Kuis agrees to pay their debt and hires them to work for her. Ending their short career as space pirates.