Shiro is a short, old man with tan skin, thin lips, a wrinkled forehead, white hair, a white beard, and large, white eyebrows. He wears a green and orange-striped shirt with a matching green and orange-striped hat that has a white band around it. He also wears a light-green vest, a blue scarf, khaki pants, and a blue sash around his waist.
As his epithet suggests, Shiro is incredibly shy, as he was unable to confess to, let alone approach, Tama with his feelings for her. His shyness forced him to hide in the shadows and watch her from a distance. Only when she was ready to confess was he inspired to face his fears.
Shiro is also quite romantic, making Tama fall in with him just by stroking her face and saying that her skin was as polished as a gem.
Tama and Shiro have been in love since they were young, but both were too nervous to confess to the other. Shiro could only watch Tama from the shadows, as he was infatuated but too afraid to approach her. Once Tama gained the confidence to confess from Luffy and the Phantom Remedy, Shiro was inspired to do the same. The two both set aside their fears and began dating.
When Shiro was young, he met Tama, and he stroked her face, telling her how she was as polished as a gem. He wanted to approach her again later, but he was too shy to do so. He watched her longingly from a distance for years.
One Piece: World Seeker
Shiro watched as Tama sent Luffy to Spa Island multiple times to retrieve the Phantom Remedy. Once she gained the confidence to confess to her love to someone, he knew he had to do the same. Realizing that they had mutual feelings, the two began dating.
When Luffy returned from his last trip to Spa Island, Shiro and Tama told him together about their new relationship and thanked him for his help. 
- One Piece Games - One Piece: World Seeker, Side Quest: "The Phantom Remedy", Shiro confesses to Tama and becomes her boyfriend.