Annabel asks Dian to give her a moment so she can remember her lover from 10 years ago.
Dian explores the mansion and sees a large man carrying a jar filled with blood. He is presumably a cook for the mansion.
This is that servant.
He appears in Sandman Midnight Theatre on page 33 in panel 5.
Max did a great job with this portrait. As always, I love the line work on his face. Max’s approach to this is a lot less disturbing than the character in the published comic, but he managed to give him a bit more humanity, which I really like.