Assassination of Aizen! The Darkness Which Approaches

Captain Aizen is found dead by his vice captain Hinamori-kun. Filled with anger and sadness, and based on something she heard earlier, Hinamori accuses captain Ichimaru of killling her captain, and attacks him. After that Ichigo and his friends go to the tower to save Rukia, but unknowingly someone with great power is waiting to destroy them.