First five chapters is the threesome, done well. It takes a bit for them to work out the relationship and I like that it came to a real, true, threesome solution.
Second was the teacher/student and they ended up together. Enjoyed that. (Chapter 6)
Third was the brothers. really not happy about that one, because I didn't like the way it ended. Too ambiguous. I would have preferred to see that they really would be together.
Kedamono Hatsujouki!!