Juli is generally a very lively and optimistic boy. He is like a ball of sunshine, with so much positive energy in him that he has to share it to those around him (especially through encouragement). Due to the environment he grew up in, he came to love and appreciate the beauty of everything especially marine life. He considers his best friends to be the aquatic plants that grow around his home and can understand them on a spiritual level. He enjoys participating in fiestas and merry making events. Jules is also a good singer like the rest of his fellow sirens. His voice is described to be rich and soothing.

While he can be a ball of energy and the happiness diffuser, it is because of this trait that he has little knowledge in actually comforting a person. He is used to being happy that he cannot properly empathize with people however, he can be a good listener -Just don't let him give advice.

He also cares for following the rules and respect the authorities. He tends to think of both sides of the coins before making his judgement (which usually ends with him being in the grey/neutral zone) unless it concerns wildlife. He believes that the elders always knows what's best, especially concerning their safety. However, he is also very curious about the world around him making him susceptible to rash decisions and being easily swayed.