Sigma opens his mouth to speak before thinking better of it. Ah, so this wasn't the same girl who had found him half-dead with shock and had been equally startled. But she was very likely the same person, and Sigma feels gratitude nonetheless. He clears his throat and takes a step back, reading her nervousness.

"Forgive me. My name is Zero. There was once a kind young girl by your name who lived in the same District quarters as I do. She once did me a great favour, one I never had the opportunity to repay. You are new here, isn't that right?" He hopes it will be a sufficient explanation to clear away any misunderstandings.