When a soul/hime burst, it generates 10 BG for everyone in the team that goes after it. This means for a full burst, you don't need to get everyone to 100 BG, you only need the soul to have 100 BG, the first hime to get 90 (will hit 100 after the soul burst), the second 80 (will hit 100 after the soul and first hime bursts... etc), the third 70, and the last 60. This is why it's important to have your fastest hime in the first spot and the slowest in the last.