“Do you care to explain what that was all about?” Dorothy asked, after a long moment of silence.

Roman shifted his eyes to her face. “If it’s all the same to you, I’d prefer not to.”

“Roman,” she said, sharp.

Roman rubbed his eyes with two fingers, sighing deeply. “Very well.” He placed his coffee back on the table, folding his hands in front of him. “As you guessed, the little girl in the clearing was my sister.” He hesitated, and then added, “Cassia.”

“Pretty name,” Dorothy murmured.

“I . . . talk to her, sometimes. To her picture, I mean. That’s what you heard last night.” A flush of red spread through Roman’s cheeks, and he took another sip of coffee, suddenly awkward.

“What happened to her?”

“She was born with type 1 diabetes. What you just saw . . . her blood sugar plummeted unexpectedly, sending her into shock. We’d run out of insulin the week before and, with the hospitals overrun from the earthquake, there was no one we could go to for help. She went into a diabetic coma, and . . .” Roman looked at Dorothy and away. “Well. You saw what happened.”

“She died,” Dorothy said, and Roman closed his eyes.

“She did,” he added, voice quiet. “It’s why I can’t leave this city. It’s the last place she was ever alive. It’d feel like I’d left her.”

“And you thought you could still save her. That’s why we came back to this day, isn’t it? It wasn’t really about bringing medical equipment to the city at all?”

“It’s not the only reason.” Roman leaned back. The fluorescent lights caught his eyes, turning them a deep, stormy blue. “Back at Fort Hunter, you asked me why I betrayed them. Ash and the others.”

“You said we hadn’t been acquainted long enough for that story.”

“You remember.” A ghost of a smile flitted across his lips. “I know what Ash thinks of me, what he probably told you, but I only left the team because of what happened to Cassia. I wanted to go back in time and try to save her life, but the Professor said it wasn’t possible. He wouldn’t even try. I thought he was being selfish. But the old fool was right.” Roman laughed, humorlessly, and shook his head. “But that’s not the only reason I wanted to come back here.”

Dorothy was confused. “What other reason could there be?”

“You asked me about the butterfly effect before, when you saw what our future was going to become. You asked me why I didn’t want to figure out which moment changed the course of human history. Remember?”

“I remember.”

Roman looked up at her, miserable. “The moment Cassia died was the moment I first started thinking about defecting to the Black Cirkus. I didn’t actually leave until years later, but . . . if she hadn’t died, I’d have stayed with the Chronology Protection Agency, and everything would’ve been different. The Professor never would’ve gotten lost in the past, we would’ve found a way to stop the earthquakes. Everything that happened, everything that’s going to happen, all of it’s my fault.”