She was on the train, on her way to/back from school (?).
Happily minding her own business (she was reading a book), the other guys on the train took a liking to her and started groping her.
Since there are no law pertaining to fucking in moving trains, the guys fuck her. Fucking her in various positions, and alternating between her pussy and mouth (and at times, both). The guys left her once they have unloaded their payload on her body.