Cosplay Change Pure Kei Joshidaisei No Kiken Na Seiheki

Aima Imoko is a young college student with a hobby of cosplay. Luckily there is a cosplay shop near her where she would like to try on a few outfits. On site she meets a hardcore otaku shop owner who also cosplays. Both are deep in their roles and she is a bit revealing, what are they supposed to do?