As of now, Uta is indeed alive. The story hasn't depicted anything otherwise. Maybe there'll be changes in the future, but for now, Uta's part in the manga continues with them being alive.
Well, without more context, it's difficult to say precisely. 'Baozi' could be a nickname or a specific name in a certain culture or story, and 'hana' might be as well. A 'fanfic' is a fan - written fiction, so it could be about their adventures, relationship, or something completely different depending on the creator's idea.
Saya no Uta is a dark and psychological visual novel. It often involves themes of love, madness, and the human psyche. The screencaps from it might give glimpses into its unique art style and the various in - game scenarios that contribute to its overall disturbing yet thought - provoking narrative.