The keyword you provided, refers to a specific file—likely a compressed archive containing video content from the FC2 Adult Market (a popular Japanese video-on-demand service).
If a .rar file tells you that you need to download a specific "special player" to watch the video, it is almost certainly a virus. Modern players like VLC or MPV can play almost any video format without extra software. The Best Alternative: Go to the Source
If you must open a suspicious file, do it inside a Virtual Machine or a "Sandbox" environment to protect your main operating system.
Many sites that list these specific rar files don't actually host the video. Instead, they provide a "downloader" or a password-protected archive. When you run these files, they may install: To steal your passwords. Ransomware: To lock your personal files.
Indicates that the original large file has been split into multiple compressed parts to meet file-hosting size limits. The Risks of "UPD Verified" Downloads
