Neptune is a teenage boy with tan skin, having dark blue eyes and messy light blue hair that is shaved on the sides and in the back, aka, an undercut.
He wears a white dress shirt and black tie under a red jacket with a wide, upturned, black collar and a pair of gray jeans with black padding strapped to the sides. The back of his jacket displays a silver reticle.
He wears black shoes that are fastened with straps, rather than laces. Notable accessories include black fingerless gloves and a pair of yellow-tinted goggles worn on his forehead.
- In the episode, "Dance Dance Infiltration", he reveals to Jaune Arc that the reason why he refused Weiss' offer to accompany her to the dance was because of his inability to dance.
- In the episode, "New Players", it was evidently shown that, despite the irony of his name being "Neptune" (the Roman god of the seas), he is very afraid of water.
- This also serves as a reference to how his voice actor, Kerry Shawcross, can't swim.