What are some kenyan last names?

i am writing a book with a man who is kenyan in it. i would prefer Kikuyu origin because that is the origin of his first name. this is a description of him; mysterious, tall, muscular, extremely dark, 20s-30s, and he has been re-incarnated. its a fiction book okay? his first name is Gacoki (which means "he returns"). i would like last names but if you can find a better first name to fit him that would be cool.