System: My Doomsday Train - Chapter 12: Train Construction.

Going for a swim, she ends up in an ancient wild Beast World and ends up being brought home by a handsome wolf.
She wants to stick to the handsome wolf, stock some salt, farm some land, look at some handsome men and grow old like that, but the handsome wolf pounces on her every day.
What? He wants her to have babies?
NO~ NO~ NO~ There is no happy ending to interspecies marriages, hurry and let go of me handsome wolf~

- Description from Novelupdates

In a world where martial artists reign supreme, strength is everything. Unfortunately, that logic doesn't apply to a certain Florida Man.

Refined in the nuclear fallout wasteland, Leo was the strongest mutant alive. He carried an alien artifact, allowing him to exchange his lifespan for modern items. After 50,000 years of solitary life in a humanless world, he collected enough lifespan to transmigrate to another habitable world.

Leo was later thrown into a mysterious planet. He soon discovered that his body produced radiation, and it mutated the surrounding plants and grasses. Worrying that he might ruin the beautiful planet, he chose to live in seclusion.

Unfortunately, the local population soon discovered his existence, and a misunderstanding ensued.

After Xia Feng transmigrated, his heart was mysteriously removed.In its place, a defective demon heart capable of sustaining life only for eighteen years was implanted.This is a magical heart that can sync with the power level of its target.To stay alive, he bound himself to the ultimate villain of the future, a Destructive Witch who was destined to destroy the world.The stronger the Destructive Witch becomes, the stronger he becomes!Thus, Xia Feng realized, it's not my fault for stirring up trouble: “Miss Witch, I admit you're strong, but not strong enough!”

Lacy was raised at a governmental school since the age of 9, now that she's 18, she is to be mated to an Alpha. The thing is, she already loves an Alpha, one whom she met on an online gaming platform.