Though her title might make one think otherwise, let's get one thing straight - Miranda is a bitch. Not even in the way that Piastol is a bitch to fight. No, Miranda is a bitch in the purest sense of the word. Her strong attitude as one of the Sisters of Deningrad is what caused the Silver Dragoon Spirit to leave Shana and jump ship for Miranda, a much more powerful personality, thereby giving Miranda the power Shana had once held. Miranda's status as one of the Sisters, combined with her newfound Dragoon powers, allowed the group of heroes to fight off the Divine Dragon, and her continued assistance (despite the bitchiness) was greatly appreciated as the group reached the end of the journey. But here, Miranda nearly lost it - on the Moon, she fought an effigy of her mother, and her heart nearly broke. Crying for the first time in nearly forever, Miranda's heart finally grew softer and more forgiving (which also incidentally fixed that blood pressure problem she was having). Having changed herself for the better, Miranda was instrumental in defeating the horrible Melbu Frahma, restoring peace to the world and rebuilding Deningrad.
The White Silver Dragoon Spirit contains magic powers that Miranda has proven are quite effective in the lower divisions. She's fairly quick, and though physically frail, her magical resilience is top notch. Backed up with plentiful healing and th parasitic summon bearing the name of her spirit, Miranda's sure to make some more splashes...once she gets in again.