Trial Balloon Question

Anders: Yeah, and then you wake up one day and discover you're another thing. Still doesn't change who you really are. Still doesn't change the fact that I love you, no matter what.
Starbuck: You are a better person than I am, Sam, because if I found out that you were a Cylon... I would put a bullet between your eyes.

—Battlestar Galactica

Alice has been going through some rough times lately. She's discovered some upsetting facts about her likes, lifestyle preferences, or even species that aren't exactly conventional. It can range from the silly, like being a fan of a bad sports team, or a Real Life conflictive issue like being a lesbian, or not actually being human. Of course, she'll go through a lot of personal anguish over not being what she thought, but she'll usually come to terms with it. This trope is about the fact that she's now keeping a huge secret from those around her, and she wants to let it out rather than live a lie. Complicating matters is that mainstream society, or at least her social circle, does not think this is kosher. They might even kill members of that group/species/whatever on sight.

So she asks Bob a Trial Balloon Question to test out his opinion. She asks (hypothetically, of course) if he would still love her if she weren't exactly a one hundred percent normal human. Ha! Fat chance. He'd be the first in line to cut off her head.

The truth will eventually come out, and Bob will be forced to actually decide if he loves her for who rather than what she is. If enough people reject her before and after the revelation, she may switch factions entirely either due to disillusionment or for simple survival.

If the answer to Alice's question is "Mostly", expect it to be followed with Have You Tried Not Being a Monster?

If the answer is "Of course I'd still love you," Bob's reaction when learning the truth could still go either way.

The only safe answer is "Meh," really, as it would mean Bob couldn't care less, and this really wouldn't change anything at all.

Compare I Have This Friend, Comic Role Play.

Examples of Trial Balloon Question include:

Anime and Manga

Happens in Scrapped Princess more than once.
More or less happens early on in the manga/anime Esper Mami. Mami has developed Psychic Powers, and the teacher caught her daydreaming about being a superhero. He quickly warns Mami's parents that she's letting her imagination run away with her, and they'd better stifle it for her own good. So when Mami comes to her parents and starts querying about their thoughts on special abilities, they mention that in the old days, people with such powers were known as "witches", and if they existed today, well, we'd just have to Burn the Witch, wouldn't we? Mami decides not to tell her parents, and as of the end of the anime, has still not come out to them. (Not sure about the manga.)
In Genesis of Aquarion, Sirius asks Reika what she would do if it turned out that there was a Shadow Angel in their midst. She thinks he's talking about a mole, so she reacts rather aggressively to the idea. When she finally finds out the truth she decides she doesn't care, but she hesitates a half-second too long to prevent his Face Heel Turn.
In the third season of Is It Wrong to Try to Pick Up Girls in a Dungeon?, Bell asks Ais a hypothetical question about what she would do if she ever met a self-aware, intelligent monster in the Dungeon. Her reply convinces him to refrain from revealing the existence of self-aware, intelligent monsters in the Dungeon.

Comic Books

In an issue of Ultimate Spider-Man, in a crowd scene with various different conversations running in the background, one is of a couple asking each other a series of "Would you still love me if I was..." questions, one of them being a reference to Spider-Man enemy Scorpion.
There's an issue of a Silver-Age Lois Lane comic where Lois uses a transformation device to become African-American for a day, and on the cover/inside she directly asks Superman if he'd still love her if she wasn't white. Surprisingly progressive for the time, anyway, just for raising the question.
A variation in Power Pack: Julie's mother tells her she'd still love her "even if you sprouted wings and flew". Well, while Julie never grows wings...

Film

Eli in Let the Right One In asks Oskar, "Would you still love me if I weren't a girl?" The audience assume Eli means "I'm a vampire", but actually Eli was given an involuntary, non-surgical penectomy.
Inverted in But I'm a Cheerleader, where everyone except the main character knows she's a lesbian: It's her friends and family who ask her the question and she doesn't react well.
Happens in Cactus Flower, when Toni tells her lover Julian, who had to tell her something, that she'll forgive "anything but lies". He was actually planning to confess that he'd been lying to her from the beginning about his nonexistent wife and children.

Literature

Older Than Radio example: In Charles Chesnutt's The House Behind the Cedars, the main characters are a mixed-race brother and sister, John and Rena, who work their way up in society by passing for white. Rena tests the loyalty of her white fiance by asking if he would still love her if she were black. Unfortunately, he misunderstands the question, and when he eventually discovers her secret he rejects her.
Friday by Robert A. Heinlein features a plot twist like this, where the eponymous character asks another member of her, um, "line marriage" (it's complicated) if she would still be accepted if she were a "Living Artifact" (the story's term for a person bio/gen-engineered from scratch). The revelation ends up breaking the family apart.
- Later on Friday puts the same question to a man she's planning to have casual sex with, only for him to do a runner—it turns out that he's also an Artificial Human, and he assumes from the question that Friday would be prejudiced against him.
Sophie Kinsella's The Undomestic Godess has a main character who's a lawyer, but currently working as more of a maid, and the guy she loves hates lawyers.

Live-Action TV

In Battlestar Galactica, Anders says he'd still love Kara if she was a Cylon, and she replies that if he were a Cylon she'd put a bullet between his eyes. Little does she know that he is a Cylon, and that wasn't exactly what he wanted to hear.
- It happens in season 1 with Caprica Boomer (Later known as Athena) and Helo, after she decides to run away with him for real. She suggests Cylons can, y'know, love? And maybe they were misguided in nuking the colonies? Helo's "No, they knew perfectly well what they were doing, they're just machines" visibly upsets her before she hides it.
- In both of these cases Starbuck and Helo decide they love them more and accept their partners for what they are. Kara violently defends him and Helo bandages up Boomer after shooting her. In his case, her being pregnant helped turn him around.
In the Season 2 Smallville episode "Visitor", when a delusional Freak of the Week claims to be an alien, Clark casually asks Chloe and Lana how they feel about the possibility it's true. Chloe thinks it would be cool; Lana finds it scary.
- Yet Clark continues to want to admit his secret to Lana, instead of Chloe. The latter of whom later finds out in Season Four and accepts him completely.
In the second to last episode of the J-Dorama, Akai Ito, Yuri lies to Natsu, telling him she's not 4-months pregnant. She then asks what he would do if she actually was, and he does not respond in the way she would like (he would have her abort).
On Will and Grace, Leo grows bored of living in New York and wants to go back to Doctors Without Borders in Cambodia, but he has to tell Grace first.

Leo: Grace, you'd want me to be happy, right?
Grace: Not if it affects me in any negative way. [smiles sweetly]

On That '70s Show Eric says he and Donna should keep their engagement a secret. To demonstrate, he asks Donna's father what he'd do if they got engaged. The answer is "I'd kill you", prompting them to keep it a secret for a while.
In the season 1 finale of Breaking Bad, Skyler discovers that her sister has been shoplifting. Her husband Walt (who just robbed a chemical depository in order to make meth, while claiming he was away at a Navajo sweat lodge), asks her what she would do if it was him. She says she hopes she never has to find out.

Theatre

Used for comedy in Oscar Wilde's The Importance of Being Earnest.
In Little Shop of Horrors, Seymour was only keeping Audrey II (the plant) alive because he thought that if it died Audrey (the girl) wouldn't love him. He asked her if she would still love him, and she said that she definitely would. This is presumed to be an honest response but it is never confirmed because she dies.

Video Games

In Castlevania: Aria of Sorrow, Soma asked Mina if she'll still like him if he's Not Himself. Confused, she told him that no, she wouldn't if he changes too much. Unlike most examples, she immediately realizes that something is amiss for him to suddenly ask that, but doesn't figure out what exactly prompted the question in the first place (considering Soma tends to run off if she tries).
Played with in Tales of Symphonia-- Lloyd skips having the question asked by Colette- and in two cases directly tells her that no matter what happens to her or what she becomes, he will never treat her any less.
- Colette later repays the favour by reminding Lloyd he's still him after he finds out his dad is Kratos.
- Also played with/subverted a bit with Genis to a degree. In one of the skits, Lloyd is ranting about how much he hates Desians (Half-elves), and how much better the world would be without them. Genis, also a half-elf (though posing as a full-blooded elf; (Half-elves... aren't well-liked in Symphonia's world... it's complicated), asks him if he thinks the world would really be better that way. Then comes The Reveal that Genis and his sister are in fact half elves aaaand... Lloyd doesn't care, they're still friends and all that jazz.
Veronica in Fallout: New Vegas tells the player character she had a run-in with the Brotherhood of Steel and asks them to fill her in. There are a variety of possible answers, ranging from (paraphrased) "Don't they shoot lasers from their eyes?" to "I know enough to kill them when I see them." Once she's a companion, she reveals that she's a member of the Brotherhood herself; the player has another variety of reactions correspondingly.

Western Animation

In an episode of The Simpsons, Maggie runs away from home whilst Marge is on vacation. When Marge calls home, Homer takes the opportunity to put up a test balloon by asking how she would feel if the dog ran away. Marge reacts with horror. Homer finds this discouraging.
Happens in Megamind, though Roxanne says she wouldn't mind the actual alien features and rejects Megamind based on his actions.

Real Life

A glurgy Urban Legend has a mother and father getting a letter from their son in the service asking them what they'd do with a friend who had had his arm and leg amputated and had nowhere else to go. The parents said they wouldn't be able to take such a friend. The next letter they get is one stating that their son is dead from suicide. When they get to the morgue, they find their son...with an arm and a leg amputated.
- There's a sci-fi short story with exactly that plot (but in space, naturally).