Tensei Ningyo Hime wa Awa ni Natte Kietakunai

Also known as: 転生人魚姫は泡になって消えたくない, The Reincarnated Little Mermaid Does Not Want to Disappear as Foam, Little Mermaid Fantasy

by Mio Nanao, Rei Touma

One day, an ordinary college girl finds herself reincarnated into the world of "The Little Mermaid," a fairy tale she read in her previous life. She didn't particularly like the prince (because she didn't know him at all). But! In order to survive and not fade away into a pile of foam, she is going to do everything in her power to win the prince's heart! I don't want to die! (Source: Manba, translated)