Are you suggesting all boys who have premarital sex should go to prison for six months if the girl's parents find out? Personally I prefer Exodus 22:16 (wonder how society would be different if it were still common practice?)
Since this is an appeals court case, the most damning evidence the prosecution has is regarded as fact; the nature of the appeal is, essentially, "Even if everything the prosecution alleges is true, the defendant's actions would not merit the charged faced." The only way the girl's utterances "I should be going now" and "I need to go home" would be relevant would be if they were the strongest requests (verbal or physical) she made that the boy stop. And frankly, the notion that a girl who was raped for 90 seconds wouldn't come up with something more emphatic than "I need to go home" is absurd.