An adult friend of mine, is dating a minor, age 17 years 9 months. (Wisconsin) They know the problems with their ages. They are emotionally close, but not having sex until 18. Is there still a legal issue here? Can he get into trouble for dating? How would anyone know if they were or were not having sex. What if they were, couldn't they both deny it? What are the risks here? Is dating a minor illegal?