Aquarius (宝瓶宮のアクエリアス) from Fairy Tail

Appearance:

1girl,black eyes,long hair,blue hair,very long hair

Mermaid Form:

earrings,breasts,swimsuit,bikini,jewelry,bikini top only,bracelet,armlet,circlet,large breasts,medium breasts,monster girl,mermaid,scales

Human Form:

breasts,jewelry,large breasts,armlet,swimsuit,earrings,bikini,bracelet,circlet,bikini top only,blue bikini,choker,hoop earrings