“Please give your vital energy to Lily.”

One late night, on his way home from the station to his apartment, the protagonist hears the sound of a girl crying under the bridge.

Although the area isn’t particularly unsafe, it’s certainly not a safe place for a girl to be alone at such an hour.

Unable to ignore it, the protagonist makes his way down beneath the bridge. There, he finds a succubus curled up inside a cardboard box, hugging her knees.

Through her tears, she begs him to let her perform an energy drain (life-force absorption).

The protagonist reaches out his hand and says: "If you don’t mind me, I’ll help you however I can."

And so begins the two of them’s shared life together.