The chapter opens with a flashback to the night of the fireworks at the Hiromi's house. It's the day of the party, and Hiromi has invited his sister to come over and have a little party with him. She's not invited, but she's happy to oblige. Hiromi tells her that he's going to set up the fire works for her birthday party the next week, and that he doesn't want to set it off with an adult. He wants to make sure everyone has a good time, and he wants to take care of her.