First published in Shogaku San-nensei magazine in 2000. The commemorative first volume of the Little Mermaid Series, depicting a beautiful ocean world filled with colorful mermaids. Set in a small seaside town, this beloved comic returns, chronicling the love and adventures of Mio, a shy girl who adores the sea and fortune-telling! Through her encounter with the mysterious fortune-telling cards "Marine Tarot," which grant the power to transform into a mermaid, Mio discovers the boundless power of the vast ocean... and the great courage that dwells within the heart of a small human...
Youko, who is about to turn 43, is a "kodomobeya oba-san" ("middle-aged woman in a child's room") who still lives in her parents' house. She is part of the "Employment Ice Age" generation, and she and her mother lead a fairly comfortable life together while she continues to work part-time in her hometown. However, Youko's best friend, with whom she had promised to remain single, suddenly announces her engagement. Feeling lonely and left behind, Youko starts using a dating app to meet new people... and finds a whole new world out there. (Source: Densho Bato, translated)