Aya is a spirited girl who calls herself a warrior of justice and practices martial arts every day. She is stubborn, refusing to take no for an answer, and makes fun of Doppo Kunikida often. She seems to value helping others and is willing to sacrifice herself for the sake of others. Aya is quite bright, able to deduce whatever is inside the coffin with Ōchi Fukuchi to be possibly the source of the global vampire outbreak, even by seeing it only for the first time. Smart, kind, slightly sassy.