Rin Ichikawa is an artificially engineered human created by the Wet Prope military project, designed for unquestioning obedience. Genetically modified, she serves as a mecha pilot within the Alta Mira Agency, operating specialized combat units called Battle Soles or Skelters to defend against extraterrestrial threats. Her physical profile includes a height of 165 cm, weight of 48 kg, and distinctive features such as hair antennae and hair ribbons.

Her primary mission involves repelling hostile squid-like alien entities threatening Tokyo. As part of an all-female pilot unit, she is trained under Commander Otsuya Funagai. Rin's engineered nature and conditioning prioritize absolute compliance and mission execution above all personal considerations.

A significant narrative element explores Rin's developing romantic feelings for Otsuya Funagai. These emotions create internal conflict, clashing with her core programming of absolute obedience and efficiency. This tension introduces complications that potentially jeopardize operational objectives, highlighting her struggle between artificial conditioning and emerging human emotions.

Her existence is defined by her background as a genetically modified soldier and her involvement in high-stakes combat scenarios.