The protagonist is an orphan, and he finally has a career with his lover who has been dependent on each other since childhood. They are traveling on the beach beautifully, but they encounter a tsunami.
In a daze, he traveled to a world where he could cultivate immortality. But he didn't want to be separated from his lover, and thought to see if he could kill himself and go back, but in the blink of an eye, his lover came too.
This article is also called "Traveling through Time and Space with My Husband to Cultivate Immortality after Death"
Concept: Ancient Fantasy, Cultivation of Immortality