So, things became even smoother, and the bad sister, Tomomi, truly became Omomi.
That is until the couple, Mr. J and Mrs. Y, were invited on a vacation to Asahikawa, where they ran into a classmate who had an extraordinary relationship with Omomi. At least for a time, they had had feelings for each other and nearly became a couple, and this unlucky classmate also happened to be a police detective, whose daily job was to constantly doubt others.
This detective classmate ran into his 'first lover,' 'first love' after more than a decade and was obviously very excited. He probably couldn't help but say something when greeting her, something that only the two of them knew the real meaning of, but Tomomi wasn't the real Omomi and directly answered incorrectly, arousing the detective's suspicions.