At 22 years old, Princess Mercury is a wise and intelligent young woman. She stays determined to her lifelong mission of maintaining peace in her kingdom, and leverages her knowledge to protect her brother, Prince Serenity.

Mercury and her siblings are not related by genetics or blood. Mercury, alongside Venus, Mars and Jupiter, as the reincarnated holders of their respective planets' star seeds, are adopted by Queen Selene per tradition, and Serenity is a genetic clone and the only natural son of Queen Selene conceived through the Cosmic Force.

She carries the qualities of elegance and knowledge. She is experienced in robotics, artificial intelligence as well as other fields of sciences, technology and engineering. Some of her projects can be considered eccentric, or even weird or crazy for others, and she sometimes jokes that she is a bit of a "mad scientist" herself.

Outside of her academic career, Princess Mercury is a Chess enthusiast. She has been recognized as the best Chess player in the kingdom.

At 22 years old her height is at 5 feet and 7 . She is especially compassionate towards those who she love, and is in general an amicable young woman. She has blue short hair, and wears a cerulean gown, and a pair of blue boots.

She can transform into Sailor Mercury, the analyst of the Inner Solar system Sailor Senshi, and manipulate powers of water and ice.

Her figure is quite average for a young Lunarian woman of her age.