For me it's the thing where two characters are clearly attracted to each other but don't want to say anything due to nervousness, professionalism or whatever, and the writer wants to "hint at" it, and so bring in a character - usually a psychic or robot - to (always in front of both of the characters in question because the one who is being talked about has to see) bluntly go "your mind harbours feelings for that character" or "you love them, I can see it in your mind" or "I detect a strong reaction in you when you're around this person". It's been done on everything from The X Files to Starfox Adventures to Metal Gear Solid and it's the most lazy, hamfisted non-technique in media in my book.
Our male hero lead gets introduced to a group of normal people to aid him on his journey. All are pretty bland people except for the one absolutely strawberry floating drop dead gorgeous dark haired olive skinned big fitted athletic woman. She's more of a background character. She turns up at his hotel room, he's about to float her! BUT WAIT, SHE'S TRYING TO KILL HIM NOW! SHE'S BOTH SEXY AND DANGEROUS