Fucking Teacher for an "A"

Samantha is a model student, but when she is suspected of cheating on an exam, she must prove to her professor that she wasn't. The professor needs a lot of convincing and Samantha, though infatuated with him, isn't sure if she is willing to submit to his every desire. When it's over, though, she really hopes she gets an "A" for effort. This story involves intense sexual situation between adult characters.