During breaks in the main story, the game will switch to the Interlude Phase. During this phase, Black Butterfly Outbreaks will occur within the city. There are also character events that only occur during this phase. Talk to the characters marked with a green exclamation point to trigger these events.
Talk to Simon to accept quests. These are sidequests entirely different from the main storyline so you can take them to earn extra exp, Blood, libra, and items. The story won’t proceed unless you continue the scenarios where you left off so use Interludes to complete as many sidequests as you can while also earning skill points through Daytime Activities and Day Quests.
When all four scenarios in a chapter reach 100%, you can proceed to the next chapter.