Barium Shirakage

The star of that white liquid everyone has drunk at least once for "barium examination." Essential in medical settings as a contrast agent that visualizes the digestive tract by blocking X-rays. Also the identity behind green fireworks, and lurking in smartphones as piezoelectric ceramic (barium titanate). Heavy and highly reactive, but shows a gentle side when neutralized as barium sulfate. A late-40s man in a white coat with glasses. A dependable supporter with a strong sense of responsibility, supporting from behind the scenes.