Erio Towa (Denpa Onna to Seishun Otoko ) is Makoto's (Protagonist of the story) first cousin. She disappeared the previous June, while she was a first-year in high school, and went missing for six months. When she reappeared that November, she had no memory of what happened during that time. She also became extremely fascinated with aliens, believing herself to be an alien investigator monitoring humanity.
After an incident where she broke her leg, she started wrapping herself in a thin quilt mattress. Erio is almost always barefoot, even when she's outside. Initially she is soft spoken and unsociable but eventually opens up due to Makoto's influence, which also included disproving her delusion of being an alien herself.
She is reluctant to return to school, so she gets a part time job at her great-grandmother's convenience store and even joins a pick-up baseball team to spend time with her cousin. Her birthday has apparently been forgotten, but her family decides to celebrate it on June 7, the day after her mother's birthday. You can be Erio's buddy and celebrate her birthday every 7th of June. Make her more sociable by spending more time with this comfortable dakimakura pillow!