Marcel Atreides is the husband of Rosa Atreides and step-father of Jowy Atreides. Because Jowy was a child from Rosa's previous marriage, Marcel never regarded Jowy as his own. Jowy was not treated kindly by Marcel and his son, Marco, and both often expressed their dislike for Jowy.
Marcel disowned Jowy predicated on the belief that he was a Jowston spy and refused to let him see his mother, stating that Rosa didn't wish to see Jowy. After Jowy became King of Highland, Marcel left Highland along with Rosa and Marco and relocated to Harmonia, since he feared retribution from Jowy, whom he had treated poorly during his childhood. It is presumed that Jowy hasn't seen Marcel or his mother since his disownment.
Marcel was known to enjoy reading history and kept a library of books on ancient history, especially books on the ancient Sindar race.
- When Jowy, Riou, and Alex were exploring the Sindar ruins behind the White Deer Inn, Jowy was able to recognize the various inscriptions as Sindar. This is because he was somewhat familiar with the Sindar written language from books that Marcel kept in his library.