This trope describes the situation where a character with a Secret Identity pretends, in their civilian guise, to be friends with that identity. To put it another way, the character pretends to be friends with him/herself to keep up the illusion that the Secret Identity and the civilian identity are two separate people.
Doing this is usually necessary when the character is dropping a lot of clues. If the local hero spends a lot of time protecting Joe Shmo's family and loved ones, or Joe knows a surprising amount about the local villains, or Joe is always talking about how great the hero is, eventually someone will get suspicious. Short of revealing his secret, the best way for Joe to explain his special treatment and inside knowledge is to simply say: "Well, Captain Order? I know him. We hang out."
This strategy has some risks. One of the main reasons a hero wears a mask is to protect their loved ones. If the character's civilian identity pretends to be one of those loved ones, the hero's enemies will trip over each other trying to get to the civilian. It helps if the character frames the relationship as either casual or strictly professional, and informs everyone that they don't know who the hero is beneath the mask. Even so, there's still a chance they could wind up on the wrong end of Bruce Wayne Held Hostage or I Have Your Wife.
See also But He Sounds Handsome, Loves My Alter Ego, Charlie Brown from Outta Town. Contrast Actually, I Am Him, where the character pulling the trick has no Secret Identity to speak of, and can only fool strangers who don't recognize them. If you see something similar to this trope in Real Life, it's probably Alter-Ego Acting (type 1).
- Bruce Wayne often claims to have a cordial relationship with Batman to explain why the Caped Crusader shows up to his rescue so often. Eventually, Batman Incorporated has Wayne publicly financing Batman's hero work and his newly-expanded organization of subordinate heroes around the world.
- Depending on the continuity, Iron Man is officially an employee of Stark Enterprises and is Stark's bodyguard, so Stark made the suit for him.
- In early Marvelman strips everyone knows that in order to get a message to Marvelman you should contact Micky Moran, a copyboy at the Daily Bugle (not that one).
- Paperinik (a.k.a. Phantomias) is a very close friend of Donald Duck.
- PS238: "Friend" might be going a bit far, but the kids know that if they need to contact Moon Shadow they can go through Tyler.
- Spider-Man: Peter Parker makes his living off of this trope; he pretends to be Spider-Man's friend and sells interviews and photos of himself to the Daily Bugle. (Although sometimes Spidey claims to hate that kid who makes money off him.) When he starts working for Horizon Labs, he claims to be the guy who makes Spidey's gadgets, and as the CEO of Parker International, Spidey's his bodyguard (an idea which everyone who knows his secret points out he blatantly stole from Tony Stark).
- In the Silver Age, it was well enough known that Clark Kent was a friend of Superman that he had a Clark room in the Fortress of Solitude next to the Lois, Jimmy and Batman rooms, because it would look weird if he didn't. These days, it seems to be generally assumed that everyone at the Daily Planet is at least on speaking terms with Superman, and that must include Clark, but no more so than anyone else.
- A Moon and World Apart: Variant in that it's a friend who's in on the secret making the claim — in chapter 11, when Twilight, Sunset and their new friends meet Princess Cadance in her public disguise of "Love Hearts", Sunset says that "Love here and my old foalsitter Cadance are real close". Cadance reveals her true identity to all of them just two chapters later.
- In Neither a Bird nor a Plane, it's Deku!, Hisashi Midoriya says that he works near where Firestorm operates and that he's had to deal with the New York branch of the Hasigawa Family when the topic of the Yakuza is brought up at the U.A. Culture Festival.
- Inverted in Now Kiss, where Chat Noir and Ladybug are pretending to be friends of Adrien and Marinette, respectively, so that they can talk with each other about themselves.
- The Secret Return of Alex Mack: Downplayed; Alex doesn't claim to personally know Terawatt, but publishes the first clear video of her, and claims to have been trying to get a scoop on her for six months, so she's widely known to be associated with Terawatt. Danielle Atron joins the wrong dots, concluding that Alex saw Terawatt get her powers and knows who she is.
- Played for laughs in The LEGO Batman Movie, where Batman claims to be Bruce Wayne's "roommate" so that he can have an excuse for Bruce's (his) adopted son Dick Grayson finding the Batcave under Wayne Mansion. Taken to its logical extreme when he claims that he and Bruce have joint custody over Dick so that he can take Dick on a mission to the Fortress of Solitude. note
- The Mask: Stanley Ipkiss tells Tina that he's a friend of The Mask, and agrees to arrange for her to meet him.
- The Rocketeer: Cliff Secord attempts to tell Patsy that the Rocketeer would help him rescue Jenny as FBI agents suddenly arrive and arrest Cliff.
- In Spider-Man: Homecoming, Ned accidentally lets spill that Peter and Spider-Man are friends in an effort to make Peter look good in front of a girl. An embarrassed Peter tries playing it off by "clarifying" he just knows him from his internship with Stark Industries. Nobody really buys it except for said girl, and even then, it's more likely that she already liked Peter and was using the Spider-Man angle to give herself an excuse to invite Peter to her party.
- In the Sam Raimi Spider-Man Trilogy, Peter Parker sometimes describes himself as Spider-Man's friend and unofficial photographer.
- In The Adventures of Superman Clark Kent is a good friend of Superman's; if anybody needs to get a message to Supes just contact CK at the Daily Planet and he'll be sure to pass it along.
- Superman loves the idea of Identity Impersonator in general, which usually implies at least an acquaintance.
- On the November 13, 2008 episode of The Colbert Report, Stephen Colbert tells the audience he has a "close personal relationship" with Superman, then implies that he is Superman.
Stephen Colbert: ...though we've never been seen together. Hmmm...[curls hair over forehead, takes off glasses]...I wonder why.
- Clark Kent uses this trope (as usual) in Lois & Clark. One episode in particular had some reporters find Superman's uniforms in Clark's closet, so Superman appeared alongside Clark (Martha took up holograms as a hobby in the episode) and explained he simply needs to keep them somewhere.
- Supergirl (2015): Similarly to Lois and Clark, Kara uses this, sometimes using one identity to pass along "messages" from the other. Lena is one of Kara's only friends who doesn't know the truth, so this trope comes up most often around her. Kara also gets in trouble for trying to write an article with Supergirl as her only source, which is on shaky ground when it comes to journalistic integrity.
- Wonder Woman: Wonder Woman often talked about Diana Prince, calling Diana Steve Trevor's "capable assistant" at one time and in "The Man Who Wouldn't Tell", Wonder Woman finishes a transformation by calling out "Diana! Run!" to get people to think that Wonder Woman is arriving on the scene while Diana Prince is fleeing.
- Daredevil (2015): Obviously Matt Murdock has to do this with his secondary identity of Daredevil. This results in very awkward conversations, like in the season 1 finale when Matt and Foggy are talking to Brett Mahoney about information Matt disclosed to Brett as Daredevil.
- On Mahou MUSH, Mamoru Chiba (aka Tuxedo Kamen) anonymously runs one of Tumblr's most popular and prolific unofficial fan/info blogs on Sailor Moon and her allies, featuring pictures, 'sighting' stories, commentaries, and egregious shipping. He doesn't claim to know Sailor Moon or Tuxedo Kamen, merely to be a fan, but the general concept still applies.
- Prince Adam in He-Man and the Masters of the Universe (1983) claimed to know his alter-ego, He-Man. He would often pretend to cowardly flee from a dangerous situation to tell He-Man that everyone else needed help, when he was really just going for a secluded place to transform.
- Princess Adora also did this with her alter ego, She-Ra: Princess of Power.
- VeggieTales: In "Larry-Boy and the Rumor Weed", the mayor of Bumblyburg calls Larry to ask him to send his pal Larry-Boy after the titular Weed.
- When The Treasure of the Sierra Madre was adapted into a film, author B. Traven sent a friend of his, Hal Croves, to be a technical adviser on the film. Reportedly, "Croves" was actually Traven himself.
- Daniel Handler claims to be the public representative for Lemony Snicket, the author of the A Series of Unfortunate Events. In truth, Handler wrote the series, and Snicket is a pen name (and an actual character within the series).