Prometheus is a sun homie that Big Mom summons from her right hand. Prometheus is a large sun, though is of course much smaller than an actual sun. It has several sunrays surrounding it. Its eyes and nose are very close together, and are small compared to its large mouth. It has blushy, rosy cheeks. When it uses its power, its appearance changes, and it resembles a fireball while its facial features remain.
Prometheus is very loyal to Big Mom and will come to her when she summons it. It also cares about the safety of the citizens in Totto Land and may even question Big Mom and beg her to cease if it sees her tantrums are causing harm to others, but due to being a homie it can never physically go against Big Mom due to fearing her powerful soul as all homies do. In conjunction with Zeus, Big Mom can use Prometheus to change the weather and create massive storms. When Urouge invaded Whole Cake Island and defeated Snack, Charlotte Linlin had Zeus and Prometheus create a large thunderstorm as Cracker sailed in to defeat Urouge. Prometheus danced with Big Mom and many other homies as she asked for a status report on the preparations for Vinsmoke Sanji and Charlotte Purin's wedding. During her rampage on Whole Cake Island, Big Mom grabbed Prometheus and threw it onto the ground. Reappearing in the sky, the sun tried to tell Big Mom to stop, but she did not listen. When Monkey D. Luffy invaded Whole Cake Island and defeated Cracker, Prometheus and Zeus created a massive storm while Big Mom's army marched to attack Luffy.