The "plaintiff" in the trial of criminal cases is the public prosecutor, who is appointed by the procuratorate to appear in court as a state prosecutor and accuse the crime. In some cases, there will be people who rely on criminal incidental civil action, that is, victims of criminal cases.
Whether there is a defender or not, the defendant in a criminal case has no right to ask questions in court, but has the right to defend himself and make a final statement.