I wonder had the genders been reversed how this would play out. The teacher is female, the student is male so instead of him being raped, he had sex with her. Instead of getting a longer jail sentence, she gets effectively 6.5 years (15 years with 5 suspended, out on parole in just over 6) and she said he initiated it, somehow making him responsible.
Why not call it rape? It might not be forced but she was the adult, a teacher and a person of authority who misused her status and had sex with a minor who clearly had emotional health issues (mentioned in the case).
Every bit of this was wrong.