The story features Nao and Haruka being invited by their friend to play the Santa game in Shibuya on Christmas Eve i.e. doing good deeds for others and uploading the evidence on SNS. However, their friend fails to show up at the last minute so the two of them roam the streets aimlessly. Just then, a photo uploaded to SNS causes the two of them to be suspected of doing something which leads to a manhunt for them in Shibuya.