If the boyfriend fails to show in response to a subpoena, he can face arrest. Also, the state may be able to go forward without him. In fact, since 75%+ of all DV victims recant or refuse to cooperate almost immediately after the incident, the state is generally expecting to move forward without the victim's assistance.
At the arraignment you should be asked to plead guilty or not guilty, then the next hearing date will be set.
Florida has the following process at arraignment:
Once criminal charges are filed, you'll make a court appearance which is known as an "arraignment." If you are incarcerated, this will usually occur within 72 hours of your arrest.
During your arraignment, you'll be asked to enter a "plea" to the crime you've been charged with. Florida pleas and corresponding definitions follow:
Guilty plea: If you plead "guilty," you're admitting to the facts of the crime and the fact that you were the one who committed that crime.
Not guilty plea: A "not guilty" plea asserts that you did not commit the crime with which you were accused. After your plea, a pre-trial or trial date will be set.
No contest plea: A "no contest" plea indicates that, while you are not admitting guilt, you do not dispute the charge. This is preferable to a guilty plea because guilty pleas can be used against you in later civil lawsuits.
"Mute" plea: In Florida, you may "stand mute" instead of making a plea. The court will then enter a plea of not guilty. By standing mute, you avoid silently admitting to the correctness of the proceedings against you until that point. You are then free to attack all previous proceedings that may have been irregular.
If you plead "guilty" or "no contest," there will not be a trial. You'll then be sentenced.
During the arraignment, the court will also:
Refuse to set bail; or
Release you on your own personal recognizance, which means that the court takes your word that you will appear when necessary for later court obligations
A Nor Cal Police Sergeant
"Make mine a double mocha ...
... and a croissant!"
Walk humbly with your God
-- Courageous, by Casting Crowns