I Picked Up a Son, So How Did He Turn Into a Scheming Yandere?

[ABO + Two Male Leads + Younger Love Interest + Raising Him + Yandere and Scheming]

Lu Chuan transmigrates into a novel written by his friend, becoming a doomed villain: a brute who abuses the young protagonist, Allen.

In the original story, Allen awakens as an Alpha and personally kills Lu Chuan.

But now that he knows what happens, he can't let that come to pass. So he takes in the poor little boy and raises him with care, feeding him and soothing him to sleep, before sending him away to avoid being killed in return.

But the plan goes awry. When Allen grows up, he doesn't leave. Instead, he comes back with red-rimmed eyes. “I told you... you weren't allowed to run away.”

The little brat who once tugged on his sleeve and begged him, “Don't go,” has become the strongest Alpha, smiling as he locks the cage.

How did things end up like this? I only wanted a well-behaved son...