1. A video editing device comprising: a storage unit to store a detection target, a similarity determination condition for determining a similarity of an original video content to the detection target, and a message in association with one another; a detection unit to determine in accordance with the similarity determination condition whether or not the detection target is included in the original video content; and an composite unit to add the message associated with the detection target to the original video content in a case where a determination result by the detection unit indicates that the detection target is included in the original video content.