In the illustrations, he is depicted as a thin, fair-skinned human with dark hair (likely not too short as he often describes having to fix it after showering, and it being otherwise "poofy") While on Adastra, he wears togas and sandals.At the start of the story, Marco seems to be a relatively average person. However, over his time on Adastra, other characters (especially Neferu and Virginia) remark that he is becoming more like Amicus - becoming more confident and more prone to risk-taking.