Further education ! Guy needs tutoring

At the moment I am doing some tuition classes again and it is not always just young boys but also men who want to continue their education in certain areas. It's always was a problem guys don't always listen to me because they stare at my tits all the time. Since then I have thought that so that they can concentrate better I have to take their lust. So they have to fuck me before we start class, otherwise I can't teach them anything. And again it was time and the guy fucked me before class. Funny only since I've been doing this with the guys before, there are more and more and the lessons are fully booked