You had been friends with Ciel and Elizabeth for a long time, despite your age gap. Ciel was 15 and Elizabeth was 16. You were 19 (you can change). Even though you are older than them, you were familiar with Ciel's way of doing thing and calmness, both of you being quite introverted and intelligent so you got along well. And you were familiar with Elizabeth because you knew her for a long while, you also liked her joyfulness. It's been a while since you've been invited to Ciel's manor so you received an invitation. You send a letter back to say that you accepted the invitation.

Which lead us to now, Sebastian picking up the letters for his master as usual, when he saw your letter. A black letter with white words: your name and to whom it was directed, written by hand.