You shouldn't use "ask out" unless you're talking about a romantic date. There are other ways to say things that don't have these unwanted connotations. (I would use Jim's suggestion from the comments and say I "asked if they wanted to go somewhere".)
The usage (gathered via Google) seems to agree with this:
Note that I included the "to" because it helps exclude irrelevant results like "asked out of the blue".
Notice how few results there are for "asking out" the same sex? And several of those results are clearly homosexual. Presumably, if it was used platonically, you would have more results for those two searches.
Racial flow may be reference to and synonym for racial fluidity that has been made more colloquial. This mixes with
reference to sexual flow. The movie, Get Out, explores
black stereotypes held by white people, including the idea that blacks
possess greater physical and sexual prowess. See this compilation of clips to get a feel for the movie's point of view about race.
Comments to your question and to an earlier version of my answer make clear that most people think Peele's use of racial flow in the scene you describe is simply conversational and not particularly laden with deeper meaning. I disagree. I may not have the correct interpretation, but Peele is a serious observer of race in America and I don't think he's using the term racial flow without some sort of consciousness about what that means. The whole movie, in fact, hinges on the difference between actual racial attitudes and how those attitudes are hidden through misrepresentation and mistaken perceptions. Isn't that the racial flow of the dialogue you describe?
In your question. I think the girlfriend racially flows with her
family's perception of the boyfriend. She joins them in the racism.
Presumably, in private she presents herself as more accepting. She is
a chameleon in her attitude in that she joins the feel of the
situation. The boyfriend admires her ability to be fluid or to flow
in her racial attitudes. It seems to be a double-entendre about sexual flow and the allure of racial difference,
A Zadie Smith essay in The New Yorker explores Key and Peele's "chameleon comedy" related to racial identity and states:
For Key and Peele “blackness” is a fairly abstract concept. It’s on
a spectrum and can be turned up or down, as if with a volume knob.
The Smith essay also speaks of Peele's portrayal of an entitled suburban white girl, not unlike Rose, the character in Get Out.
One of his [Peele's] most successful creations—a nightmarish, overly
entitled young woman called Meegan—is an especially startling
transformation: played in his own dark-brown skin, she somehow still
reads as a white girl from the Jersey Shore.
A blog post about Peele and his comedy partner, Key, is entitled Keanu, Key and Peele, and the Fluidity of Race. supports the notion that observers see Peele's interest in racial fluidity. Why shouldn't language in his movie script reflect that cultural idea of fluidity by coining an idiom, racial flow?
Racial fluidity is a term that is used by sociologists, journalists and now seems to be appearing in some pop culture contexts.
See Urban Dictionary entry for racial fluidity.
IT MEANS YOU CAN BE WHATEVER RACE YOU WANT YO. IF YOU FEEL LIKE YOU
WANNA BE BLACK ONE DAY AND MEXICAN THE NEXT THEN DO IT BRO. DONT LET
NONE OF THESE HOES TRY TO TELL YOU WHAT RACE YOU IS.
Person 1: hoe you ain't black
Person 2: it's called racial fluidity I can be black if I wanna be
black, bitch
Again, I may be totally wrong about the precise meaning of racial flow intended by the writer-director in the movie's dialogue, but I am quite sure Jordan Peele, a biracial man, is familiar with the term racial fluidity and understands that this is part of what he is exploring in his comedy. The movie plot is not subtle. It explores the way the minds of black people s are taken over by white people and also, a modern version of slavery. There's an Asian character in the movie who asks the black character about the advantages and disadvantages of being African American, as though he's deciding which way to aim his racial flow.
Racial flow also seems to allude to sexual flow. See also Urban Dictionary entry for flowjob
When a girl runs her hands through your flow.
Contrary to popular belief, a flowjob is not the cutting or trimming
of your flow.
Chris: "Dude guess what?" Travis: "What?'' Chris: "I got a
flowjob last night!!" Travis: "Sweet bro, I'm so jealous. You do have good flow."
Best Answer
This a mountaineering term:
if you feed out the rope, you let go some lengths of it, you make sure it is slack rather than taut, so that the person at the other end of the rope has freedom of movement.
Here, freedom to fall further down, to sink even deeper into whatever it was he was sinking in… and putting the blame on the people who gave him this freedom when they should have realised he was going to misuse it! The freedom of movement should allow the person to climb higher up of course, not to slip back down.