Ayaka Matsumoto is a genetically engineered female pilot created for the Wet Prope military project. She stands 155 cm tall and weighs 45 kg, with distinctive pink hair and gray eyes. Despite her teenage physical presentation, her registered age is 3 years old. Ayaka pilots the purple Skelter Titan-05, a specialized mecha unit armed with a primary sword weapon deployed to combat hostile squid-like alien entities threatening Tokyo.

She serves in a squad commanded by Otsuya Funagai alongside fellow genetically engineered pilots Rin Ichikawa, Misaki Kashima, Konomi Tamura, and Midori Matsumura. Ayaka is frequently observed spending non-combat time with Midori Matsumura. Her combat role involves participating in interactive command assist battle sequences where her performance directly influences mission outcomes.