Once in control, follow the path until the tower starts beaming on you. Quickly move between the platforms to avoid getting hit by the beam and swing your way to the tower. Once inside, move forth until you reach the area where the boss is located.
Boss: Bob Barbas
First, take note of the three red panels on the ground. These act as energy conduits that supply energy to the boss and makes him invulnerable to damage. You have to smash them using the Eryx's stomp attack. The boss has three life bars so the battle is divided into three phases.
For the first phase, you have to destroy one conduit to make him vulnerable. I suggest saving up your devil trigger in the last phase. Keep attacking him until his life bar is depleted and an angel lift target appears on his eye. Pull yourself there and you'll be transported to another area, where you need to take out enemies. Use this chance to increase your style gauge and to get more orbs.
Repeat the same process for the second phase; only this time, you have to destroy two conduits before he becomes vulnerable. Finally, you have to destroy all conduits over and over again until he becomes vulnerable. You may want to activate your devil trigger at this point to deal massive damage and kill him. Defeating this boss also unlocks a new weapon, called the Aquila.
Bob Barbas, now taken off the air.