Marco has abandoned his family, friends, girlfriend and goals to live as Star's "squire" (which is not even a real title) in a different dimension where everybody ignores him unless he wears a dress.
He is constantly putting his life in danger while Star dates another guy and even if he has a chance to start a new relationship, it ends up in bad terms because he must stay with Star 24/7.
His character is pointless and his actions have no importance in the plot. At least, Moon and Eclipsa care about him.
PS: how come nobody has added pic related to the cuck Star list.