(often cataloged online under release or tracking codes like engrar001 ) is a cult-classic adult visual novel and eroge created by the independent developer Yosino (ヨシノ). Released in the mid-2010s, this title carved out a specific niche within the adult gaming community by blending traditional visual novel storytelling with high-fantasy sea exploration and monster-girl erotica.

Throughout history and modern media, ocean monsters generally fall into three distinct archetypes: 1. Mythological & Legendary Leviathans