Cirein has a great fascination with boats, and when not gathering energy or getting himself into problematic situations with kijikaiaku, he'll oft trail various seafaring vessels on their oceanic journies. The few boatswains who can see him are frequently visited, the silver-coloured subtalleon always having many questions to pepper them with. He'll assist with daily tasks, and even gather the materials needed for repairs, all so that he can learn more of these floating manmade objects.
Despite his great curiosity and general disinclination towards combat, Cirein has a fierce, aggressive streak in him, with a powerful drive to gather energy - stronger than the average energy drive of most spirits. He handles this well, but it pushes him to work beyond his limits. Cirein's focus can be so singular, that he occasionally loses track of everything else, which has led to him stumbling over or crashing into various objects.