His technique combined the formal training of the Kano school with the naturalism of the Maruyama-Shijo movement. Sosen developed a method of painting fur using extremely fine brushes to build up layers of individual hairs. This approach created a soft, tactile quality that was unusual for the time. He avoided the stiff, symbolic representations common in earlier Japanese art. Instead, he focused on the expressive faces and lithe movements of his subjects. His work often features a single animal or a small family group against a minimal background.

Collectors today value Sosen for his ability to convey personality without relying on human sentimentality. His monkeys appear as individuals with distinct moods rather than mere decorative motifs. The neutral backgrounds and soft colour palettes of his work suit contemporary interiors. These prints provide a quiet connection to the natural world through a lens of scientific observation and technical skill. His compositions offer a sense of calm and focus that works well in modern living spaces.