Ensemble Dark Horse / Fallout

Series-wide:

• Vault Boy, the amazing retro mascot who appears in Pip-Boy images and Vault advertising. He's so popular, he even made it into Super Smash Bros.. as a Mii costume!
• Harold, who has been in Fallout 1, 2, and 3, and gone from a human to a ghoul, and then finally to an undead un-living tree thing.

Fallout:

• Dogmeat, a dog that can join your team early in the game, was so popular that he returned in every major Fallout game to date, with the exception of New Vegas.

Fallout 2:

• The Enclave, who are the antagonists of both the second game and the third, have a huge fanbase.
• Sergeant Dornan is especially notable, since despite being merely an extra, he was given a talking head and a truly legendary voice over.

Fallout 3:

• Ironically, Charon, a Ghoul, is one of the most fangirled characters. Probably has something to do with his brainwashing meaning that it's impossible for him to disobey any orders given to him by those "owning" him.
• LIBERTY PRIME (caps and bold a must) - a Humongous Mecha who makes his way through Enclave troops with no effort, throwing mini-nukes at them while spouting loads of anti-communism messages. Fans love him for being the epitome of the Lethal Joke Character.

Fallout: New Vegas:

• Boone is somewhere between this and Memetic Badass.
• Cass probably has the most Fan Art and New Vegas's fandom bicycle.
• On a more general note, the First Recon Snipers are pretty popular.
• Yes-Man counts as well - it helps that he's voiced by Dave Foley.
• Veronica has also become quite popular. This is in no small part due to her being voiced by Felicia Day and the Mojave BoS' Only Sane Man.
• Joshua Graham only shows up in the game's shortest DLC, and his bigger, active role is only by the end. And yet the amount of attention he gets is huge. Helped by the fact he's among the game's biggest badasses, what with getting thrown into the Grand Canyon while on fire and walking it off.
• Sunny Smiles (and her dog, Cheyenne, by extension), found in Goodsprings, is beloved by large portions of the fanbase. This is in no small part because she's remarkably friendly, helps teach the Courier how to survive in the Mojave Wasteland, rather easy on the eyes, and always encountered early-on in the game due to her being literally in the town the Courier wakes up from after getting shot in the head (creating a sense of familiarity with her). Many fans were disappointed that she wasn't a companion or even a romance option.
• Mr. Fantastic, the Know-Nothing Know-It-All "scientist" working for the NCR at HELIOS One, is largely enjoyed by the fans because of his utterly laughable incompetence.
• Easy Pete has acquired memetic status as some kind of hardcore unkillable God. It's in part because usually in evil runs he's the first one to get killed.

Fallout 4:

• Curie has won a lot of admirers for her gentle French accent and Adorkable/The Pollyanna personality.
• The Silver Shroud as a character is a hilariously awesome parody of 40's and 50's comic heroes like The Spirit & The Shadow, and is very well-liked for the Large Ham.
• Except for the one poor member who keeps handing you radiant quests, the Commonwealth Minutemen are by miles the most popular of the four factions despite being the least important to the overall plot. This is because many fans admire them for their Muggle Power, ability to potentially become the most powerful faction in the Commonwealth with some help by the player, their unique American Revolutionary aesthetic, and being one of the friendliest factions in the entire game. Many old-school Fallout fans also like them for how they're heavily based after the Desert Rangers from Wasteland, which the Fallout series is a Spiritual Successor to.
• Magnolia, the singer at The Third Rail in Goodneighbor. She has a mysterious past, is gorgeous and a non-companion romance option, remarkably friendly, and is even voiced by Lynda Carter! She also sings her own unique songs that Lynda Carter actually wrote for the game - all of which are pretty damn good and catchy.
• KL-E-0, the Assaultron vendor in Goodneighbor. Despite her not playing that big a role, many fans love her for her hilariously dark sense of humor, seductive voice, and surprising level of humanity. Several fans have expressed disappointment about not being able to romance her
• The Atom Cats, a gang of Power Armor enthusiasts, also get a lot of love from the fanbase despite only being part of one side story connected to a single settlement. Fans love them for being incredibly friendly, surprisingly badass (they are all wearing suits of Power Armor, of course), having unique Power Armor paint jobs, and generally being hilarious (what with them only talking like the Tunnel Snakes and conducting poetry nights about Power Armors).
• "The Grenade Guy", an unnamed, unseen NPC mentioned by Raiders in idle dialogue at various locations. He's some kind of delusional Michael Winslow-esque lunatic who escapes from encounters with Raiders by making sound effects, with his signature bit that earned him his nickname being to mime throwing grenades at Super Mutants, complete with the sound effects of pulling the pin and the grenade exploding. It turns out that this is Crazy Enough to Work, since it confuses and disorients the Mutants enough for him to make his escape, which he does while pretending he's on a motorcycle. Many players have expressed disappointment that it's not actually possible to meet "Grenade Guy" In-Universe.
• Pickman, a Serial Killer encountered during a minor side quest given by Hancock, has a significant fan following - likely thanks to his polished, handsome outward appearance and oddly charming demeanor. The fact that he only seems to prey on Raiders makes him more of a sympathetic Serial-Killer Killer also helps.
• There's also the Vault-Tec Rep, the salesman who saved the Sole Survivor's family in the prologue but himself failed to enter a Vault. Two hundred years later he's a lonely Ghoul living in Goodneighbor. After he talks about how miserable he's been since the war, most players choose to offer him a job in an outpost, which brightens his outlook considerably. The fanbase largely enjoys giving him another chance to find some honest work and make some friends after two centuries as a societal outcast.

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