Akari is a young girl that appears just as mysteriously as Hikari.
Ryo finds her and makes her part of hi family. She often thinks of Hikari as her older sister. Akari is very fascinated by living things like Hercules beetles. Akari would have had feelings for Ryo if Kimi never kept saying they were a family and nothing more in the final episode Ryo was trying to kiss Akari but she told him "were family" so that Kimi won't attract them.