He is the newest member of the Keroro Platoon and also the youngest.

Tamama is possessed with a tendency to have mood swings that border on a split personality, like his partner Momoka Nishizawa. While usually gentle and cheerful, Tamama can become a vengeful, raving maniac at the drop of a hat[2]. This change is usually accompanied by the sound of a balloon popping.

Tamama is also prone to fits of jealousy, usually towards anyone who gets near Keroro

He is male, but he's voice is so high that any girl can do his voice too.