Serge was born and raised in his village. He became a farmer, living an ordinary life. He had raised a son, eventually seeing him off as he left the village to work in another country. Living by making most of the present, he plowed his fields to make a living.
Serge is described as having a "tanned and rugged face."
Ruler believes Serge must really care for his son due to the way he tidies his son's old room despite it remaining unused. Though the rest of the home being somewhat messy, the room is pristine, free from any dust.
Sieg and Ruler come upon Serge after leaving Yggdmillennia's territory, Ruler unable to move due to hunger. Believing they are a runaway couple, Serge welcomes them into his home and feeds them. Sieg, not understanding the context, says they will be going back to free the homunculi of Yggdmillennia, Serge taking it as returning to obtain blessing for their relationship. He lends them his son's room for the night. He provides them with food and coffee as they leave the next morning, telling Sieg to take care of Ruler.
Sieg, having discussed Serge's son with Jeanne the previous night, asks Serge if he loves his son. Serge replies that his son is his pride and joy, showing Sieg a smile that shows he is rejoicing in his son's success. He bids them farewell as they proceed back towards Yggdmillennia.