The four Evoluzione Sakes all come in blue bottles, which is likely done to protect the Sake from sunlight, which can negatively impact the taste if it is subjected to too much sun. Different colored labels are used for each Sake type, and each label also has a stylized and slightly scary Oni mask, including a skull, horns and fangs. An oni is a supernatural creature from Japanese folklore, sometimes called a demon or ogre. Though they are often malicious, there are some benevolent oni in Japanese folklore, though the oni depicted on this label doesn't look too kind.
Small volume, yet high quality.