Baiu

is a Genin from Amegakure.

Chunin Exam
Baiu and his team had the unfortunate luck of confronting Gaara during the second phase of the Chunin Exams. Shigure sought Gaara's scroll and underestimated his power. Shigure attempted to use his raining needles technique but Gaara's sand protected him. Gaara then took the opportunity to confine Shigure and his team using the Desert Coffin. Gaara then crushed the Rain Genin, killing them.

Source

 * First Databook, page 20