Wis. Stat. § 948.093: Underage sexual activity.

Whoever has sexual contact with a child who has attained the age of 15 years but has not attained the age of 16 years, or whoever has sexual intercourse with a child who has attained the age of 15 years, is guilty of a Class A misdemeanor if the actor has not attained the age of 19 years when the violation occurs. This section does not apply if the actor is the child’s spouse.