This is Marincess Aqua Argonaut from YU-GI-OH!

Good at 0.7-1 weight

Tags (character): marincess aqua argonaut, double bun

Tags (clothes): silver tiara, silver earrings, cape, blue vest, aqua chest jewel, blue necktie, black corset, blue armband, see-through dress, aqua pantyhose, black high heels

Tags (clothes - extra): red garter straps, no headwear

Tags (weapon): staff, holding staff

Tags (Other): huge shell, sitting on shell, coral, underwater, air bubble, official style