On New Year's Eve, while others were enjoying family reunions, Fushimi Roku and Minamoto Tamako went out of town on a business trip to investigate a case. Kazama Tatsuya and Watanabe Shun also joined, saying they wanted to assist in the investigation.
This time, Minamoto Tamako was as determined as a turtle swallowing weight to get to the bottom of the case. She first contacted Kamei Yuusaku's superior to verify his business trip location, duration, and travel invoices.
The departure and return times fully matched the testimony records, but buying a ticket didn't necessarily mean he boarded that train. Therefore, Minamoto Tamako decided to personally visit Kamei Yuusaku's business trip location for further investigation.
Once investigated, a discrepancy quickly emerged.
