That's what it looks like....
sirius is the twin brother of ciel,
just some source but i'm not sure if it true, but the ciel whos with sebastian is not actually the real ciel, but his twin brother sirius It turns out that Ciel is ... not Ciel, but Ciel's twin brother. It turns out that the original Ciel Phantomhive, heir to the fortune and head of the family, also died while being tortured and was killed so that Sebastian could be summoned.
but it turns out that undertaker somehow saved the real ciel and that's explain the new chapter
That’s what got me thinking
Wdym not sure if it's true? It literally says so in the manga (⌒▽⌒)
Maybe sirius is our ciel real name?!