Mich. Comp. Laws § 32.1134b

Sec. 134b. (1) An individual subject to this code who wrongfully engages in extramarital conduct with another individual subject to this code and, at the time, is married to someone else or knows the other individual is married to someone else, must be punished as a court-martial directs. (2) As used in this section, "extramarital conduct" means any of the following acts engaged in by individuals of the same or opposite sex: (a) Genital to genital sexual intercourse. (b) Oral to genital sexual intercourse. (c) Anal to genital sexual intercourse. (d) Oral to anal sexual intercourse.