From the front, the Sieg figure captures the sleek, armor-clad style of Kamen Rider Den-O’s enigmatic rider. The helmet features a distinctive crest and visor, while the torso armor is layered with metallic paint that highlights panel lines and the Den-O motif. The figure stands on a balanced pose with one knee slightly bent and a sword drawn, ready for action. Fine detailing is visible in the gauntlets, boots, and belt, with subtle color accents that emphasize the character's heroic silhouette. The joints are designed to be discreet, allowing for clean display while maintaining range of motion. The overall finish combines glossy and matte textures to give the armor a real-world, collectible look. Interchangeable hands and optional sword or effect parts are included to recreate signature scenes from the Den-O series. The figure's scale and proportions align with other Bandai S.H.Figuarts in this line, making it a standout centerpiece on any shelf.

In the Den-O saga, Sieg is introduced as a skilled warrior forged from the Den-O timeline, carrying a sense of honor and a bond with the protagonist's friends. He fights to protect the Den-O world from a rogue threat, joining the main ensemble in critical battles. Sieg wields a weapon-based style that blends samurai precision with rail-sword energy, symbolizing the fusion of human courage and the kit-based powers of time-traveling Rail Liner adventures. His clashes with foes reveal themes of friendship, sacrifice, and the passing of the mantle to younger riders. As a key figure in the Den-O universe, Sieg's story intersects with multiple timelines, with his legacy echoed across episodes and films. This backstory provides depth to collectors, as the S.H.Figuarts figure aims to recreate not just the look, but the narrative essence of Sieg.