In ultimate reality, there is no man or woman. There is only Nama and Rupa. Nama is feeling, perception, intention, contact, & attention. The four great elements, and the form dependent on the four great elements: This is called Rupa. It is Nama and Rupa that sends one to hell and Nama and Rupa that prevents one from going to hell. There is a belief in the world that there is the killer and the killed. There is another belief that there is no killer and none that is killed. Both those views are wrong views because there is only Nama and Rupa. If one believed that Nama and Rupa do exist in reality then it is right view. Karma is intention. Intention is part of Nama.
According to SN 15.3, the beginning point of samsara is not evident.
At Savatthi. There the Blessed One said: "From an inconstruable beginning comes transmigration. A beginning point is not evident, though beings hindered by ignorance and fettered by craving are transmigrating & wandering on. What do you think, monks: Which is greater, the tears you have shed while transmigrating & wandering this long, long time — crying & weeping from being joined with what is displeasing, being separated from what is pleasing — or the water in the four great oceans?"
"As we understand the Dhamma taught to us by the Blessed One, this is the greater: the tears we have shed while transmigrating & wandering this long, long time — crying & weeping from being joined with what is displeasing, being separated from what is pleasing — not the water in the four great oceans."
I suggest you practice vipassana instead of thinking about such things. The time is ripe for insight- developmentdevelopment leading to Nibbana. You should also check out the biography of Sunlun Sayadaw. http://www.sunlun-meditation.net/ebooks/BIOENG.pdf