http://revach.net/article.php?id=2311

Section: Taryag Mitzvos   Category: Insight
Parshas Naso: Mei Sotah - Men Exploding All Over the Place!
The Rambam in Hilchos Sotah (3:17) tells us that when the Sotah drinks the water not only is the Sotah is put to the test but her partner in crime is put to the test as well. If she is guilty of having illicit relations, both her and her Bo’el will die from the Mei Sotah no matter where he is at the time. Chazal also teach us that even if the Sotah is innocent at the time that she was secluded with the man that she was warned about but she is guilty of a different affair, she will die from the Mei Sotah. The Mishneh l’Melech infers from the Yerushalmi that not only will she die from the Mei Sotah if she had an affair with a different man, but that man will die as well.