A high-quality 1:1 square ratio fanart for a smartwatch wallpaper featuring Kyojuro Rengoku and Zenitsu Agatsuma in a dynamic back-to-back combat stance. Use 100% Ufotable official character design accuracy for the faces, focusing on Rengoku's signature bold eyes and Zenitsu's intense 'Godspeed' expression. Rengoku is unleashing Flame Breathing with swirling, thick-bordered fire dragons, while Zenitsu is enveloped in jagged, glowing yellow electricity from Thunder Breathing. The art style must mimic the 'Demon Slayer' anime's high-contrast compositing: deep shadows, glowing embers, and cinematic bloom. 8k resolution, ultra-detailed textures, vibrant orange and electric yellow lighting, sharp line art, ukiyo-e style fluid effects. I want 101% same face as Ufotable animation.
