Daughter of Miki and Madoka, accomplished in trump, lovable flake. Mutsumi is among the physically weaker of the Amberites, fainting easily under strenuous conditions. However, she is quite cheery in spite of this, almost to the point of apparent airheadedness at times. She combines many qualities of her parents together, knowing the arts of trump to an advanced degree, and being a skilled musician. In fact, she combines the two together, with her finely crafted trump mandolin.
She has an odd fondness for watermelons. Tama-chan, the somewhat mischievous flying turtle, is her pet.
Mutsumi aided in the rescue of Ramon some ways back, as her trump skills combined with her father's were need to force a trump connection through to him. She also aided Morgan in retrieving Merehallow, the Air Patternblade. And then, she assisted Moriya in fetching Withywindle, the Wood Blade, having been recruited because that Patternblade has considerable trump powers. After that, she aided Jacqueline in the mission to Akasha to destroy Mageddon and stop two renegade Taylors, then took part in the assault on the Serpent's Horn terrorist group alongside her father.
Mutsumi appeared to have a bit of an interest in Keitaro, but is now rumored to be romantically linked with Thoric.
It would appear that Mutsumi is in fact dating Thoric and Jacqueline at the same time, to the shock of many.