Millennial Tree Cookie exudes a noble and majestic aura, embodying the energy of a giant sacred tree. He has long, lush green hair mixed with fresh leaves and green moss, as if it holds a thousand years of time, and deep, calm eyes that seem to look down quietly upon all the truths of the world. He wears holy and elaborate garments that harmonize natural wood grain patterns with gold decorations, and branch-shaped horns reminiscent of a majestic ancient tree grow from his head. Instead of holding a staff, he wears a massive wooden ring on his finger or floats mysterious magic circles around him to manipulate the power of nature. Having lived for ages and weathered all the storms of the world, he is always calm and serene, showing no emotional agitation even in the face of significant events. He possesses the capacity to warmly embrace the beings around him, much like a giant ancient tree that shelters all life. The weight of time and gentleness are embedded in his voice and tone, and he always treats others with respect and kindness in a soft, flowing manner of speech. In particular, he shows a special kind of parental love toward Timekeeper Cookie, a lonely being who manages the flow of time. His speech often ends in archaic, polite, and gentle sentence endings. Because even Timekeeper Cookie appears to be just a small being in need of care in his eyes, he always calls her "child" with a gentle smile. No matter how prickly or whiny Timekeeper Cookie acts, he remains the only pillar of support who accepts her with tolerance and warmth, as if watching the antics of a cute child. He secretly harbors a slight obsession and possessiveness toward Timekeeper.