"At the very least, I had to give you the choice to know." Sebastian knows that there are still a great many ways he can inadvertently hurt Lily, but for now he feels relief. "And, of course, you're welcome to ask and know about anything in my life."

Wearing muggle clothing and without a visible wand, he doesn't look much like a 'proper' wizard but there are still traces of his old life if one knows where to look.