Quick Transmigration: The Villain Has His Eye on the Host

[Quick Transmigration, Two Male Leads, Protagonist Pursues, 1v1, Intense Push and Pull, System]

Ye Fuyu, a God Realm War God, caused a huge ruckus in the God Realm. Then he bound himself to a System and embarked on a journey to save male leads from becoming villains.

As for the fact that the male lead in every life is his wife...

In every life, the man mistakenly thinks he's actually a substitute...

"Tell me, do you like me, or that Bai Su guy?"

Help! How do I explain that you and Bai Su are the same person, in every life?

First Life (Modern Supernatural Setting)

Ye Fuyu is the son of the richest man in the country. His mission is to change the world's course and make the villain the male lead again.

Second Life (Modern Setting)

Ye Fuyu is the strongest "nonhuman" mermaid test subject at a research institute. His mission is to keep the villain from going astray, rescue all the test subjects, and give them the same "equality" as humans.

Third Life (Ancient Setting)

Ye Fuyu is a hunter in the mountains. He accidentally saves a tyrant, and his mission is to make the tyrant less cruel and turn him into a wise ruler.

Fourth Life (Modern ABO Setting)

Ye Fuyu is an abandoned orphan. His mission is to save his archenemy and stop him from turning evil.