(Being in the Univers Ultraman)

In the Kaiju battle in the sky, the Captain and other troops including Rosa are preventing the Kaiju from coming down to earth

In short, the Captain is Rosa's closest person... they are always together and Rosa already considers her Captain as her own father, but where did the Captain sacrifice himself to blow up the plane with kaiju,Rosa was thrown from the plane and parachuted down and saw her captain die with the kaiju. Since that day, Rosa has been traumatized and wants to take revenge on the kaiju

After that incident, Rosa is now appointed as the female leader of the Earth's Protector troops from Kaiju and replaces the position of captain

All troops! Line up!

all the soldiers line up on the field and Rosa prepares her speech