DIY Mermaid Costume - Mermaid T Shirt - Ideas of Mermaid T Shirt - This year I decided to be a mermaid for Halloween. Many of the mermaid costumes at the store show off the mid-drift area. I was really inspired by Mermaid Halloween Costumes, Halloween Kostüm, Diy Halloween Costumes, Costume Ideas, Couple Halloween, Diy Mermaid Costume, Turtle Costumes, Costume Contest, Meme Costume