Niki's manga / #multiple couples(1)

1st couple: 2 students. Uke is tired defensless looking guy who works as a secretary for a sensei in the university. The seme is his"owner" and he takes care of him - visiting him almost everyday and feeding him. They used to be just friends but one day the seme hears some news that pisses him off so he jumps the uke (he likes it though). They end up together (and the seme is a possesive one but not a total maniac). 2nd couple: a student and a prince from some Arabic country. The prince is in Japan for some reason but he arrived early so he visits the university. the student guides him through the school. Then they take off to the student's apartment (the prince had guards wathching him and he wasn't happy about it). They end up having sex. After 1 month the prince comes back to the Uni. 3rd couple: A student who is also a celebrity known as "Super sadist" and his manager. The "Super sadist" is actually masochist and he tries to find a sadist for himself. He complains about it a lot and his manager takes action on his own. There is a sequel - Itsuka Kimi ni Korosareru Bonus "feathers" to the stories: There is a pervert teacher. Perveted little brother of a gitl friend of the first couple. It's still going and I seriosuly lost track...