the phrase "real talk" prefaces the delivery of some observation or argument that isn't particularly flattering to the recipient. purportedly, the speaker is about to illustrate reality rather than bullshit. the observation is always followed by a question, and presumes that the observation is fact.
for example: "real talk. you're a tracer and you sucked a man's hog. what's up with that?"
i like "no homo" better, because it always suffixes an incredibly homo statement. "i would let brad pitt fuck my anus. no homo, guys."