The teacher is pretty advanced - letting students fuck in front of her and giving her advice is cool. Sure, the student was a little shy at first, but that passed quickly. I, too, think we need hands-on sex lessons, then it will be proper and safe. And still the guy cum on the boobs of the teacher - after all, the students have to somehow thank her for teaching them.
That's exactly how it should have ended, because it's not proper for such a pretty girl to please herself, as if no one wanted her. And here she got the whole bouquet of pleasures and pleased the guy.