Novel info
Tokyo Ghoul: Starting with Kamui!

One day, Uchiha Byakuya randomly transmigrated into the world of Tokyo Ghoul. Through his System, he first obtained a pair of Mangekyō Sharingan along with both Kamui, shortly before encountering a certain green-haired girl.
(The Fic features Eto as the sole love interest, with no harem involved as well as a rather moral MC.)
Note: The Cover art isn't mine, should you be it's owner and want it removed; just send me a dm, I'll take it down.