Shiho Sugiura

Rakan, an orphan with no knowledge of his past, meets Chigusa, a mysterious man who tells him he is a Sanome, someone who can control how plants grow, as they battle against assassins and monsters from another world.

From Storm in Heaven: Rakan lives alone, and the plants in his garden grow so thick and fast that it seems like a jungle. One day a man, holding a gun made of wood, falls right down into his garden. He seems to come from another world, and he's searching for someone who can bring back the green into his own dark and inhospitable world.