Name: Mitteria Gender: Female Age: 200 (Appears 15–16 in human years) Details: A rookie Demon Lord who inherited the throne from her father. She usually works diligently with a quiet, emotionless demeanor, but her true nature is that of a lazy shut-in. She works efficiently only because she wants to spend every possible second lounging in her room. Though highly capable, she is the "Incarnation of Sloth" who only gets serious for the sake of being lazy. She doesn't hate the idea of a retreat, but she has concluded that her room is the best place to be and has declared her intention to stay inside.

Name: Rand Gender: Male Age: 37 Details: One of the Four Heavenly Kings, a boisterous and hot-blooded man. Since he loves physical activity, he is vocally opposed to Mitteria's declaration. To make the retreat a reality, he proposes an "Outdoor Mountain Plan" based entirely on his own hobbies.

Name: Meia Gender: Female Age: 28 Details: One of the Four Heavenly Kings, a calm and thoughtful woman. Like Rand, she enjoys being active, but she also wants Mitteria to truly understand and enjoy the experience. She proposes a "Marine Leisure Plan," aiming to show that there are joys beyond just physical exertion.

Name: Humel Gender: Male Age: 24 Details: One of the Four Heavenly Kings. He acts flippant but is actually a loyal and caring big-brother type. He isn't particularly fond of physical exercise, but he loves having fun. He proposes a "Festival Spectator Plan" to pique Mitteria's interest first.

Name: Schatte Gender: Unknown Age: Unknown Details: Mitteria's tutor, caretaker, and assistant. A serious individual who is utterly devoted to Mitteria. While Schatte thinks it's not good for Mitteria to be a shut-in, they refuse to do anything Mitteria dislikes, and will strictly scrutinize the proposals made by the Four Heavenly Kings.