Sex.

There are people who call spending a night alone at home, watching entertaining videos, and eating chicken with beer "sex," but that’s not sex; it’s just a meal.

Now, let’s say it together: meal.

However, for some beings, eating and sex have the same meaning. Western succubi are like that, and so are Eastern gumiho.

Since ancient times, gumiho have been known as spirits that consume men, comparable to succubi. Without regularly absorbing life energy, their lives would be at risk—it's just how their species is designed.

Of course, gumiho can absorb life energy without any particular act, but …