Kamisama No Iutoori.

Ever since his mother passed away, Hinata has been taken care of by Midori, who is as strict as he is caring. Midori’s smart, and tall, and handsome. He also doesn’t have a shadow or a reflection in the mirror. Wait… What? Hinata’s a scaredy-cat, and thinks Midori might be a ghost. But he is in fact a…?
(Source: Blissful Sin)