Black schoolgirl (high school/private school--18 yrs. old!) straight black hair, slim build, wearing traditional catholic/parochial/private school uniform: white cotton button-front shirt opened at the neck, pleated skirt, cable-knit knee-high stockings is last-minute hired to babysit OVER-NIGHT for two white kids (sex of children not important) who either trick her into letting them tie and gag her or over-power her. A neighbor or someone knocks on the door. They run and hand-gag the black chick over the gag already in her mouth to muffle her cries for help and then drag her into the bedroom and close the door before opening the door to briefly talk to the neighbor before getting him/her to leave as fast as they can before going back to their captive!
This can be in the "More Intimate" category (if her white shirt is unbuttoned to her waist to reveal her white lace bra against her dark skin--but NO sex is involved--just a LOT of "straining and struggling" and "ummphing under her gag")