I need to verify if there was a specific event in 2021. Maybe it's a special release, a rare fight, or a documentary. If I can't find a direct event, perhaps the user is referring to a rare appearance or a highlight video from that year.
Need to make sure the post is accurate. If there's uncertainty about RAR 2021, address that transparently while providing general information about the fighter. Perhaps the user meant a different term, but without clarification, proceed with the best possible information.
I need to be cautious about assumptions. If RAR 2021 isn't a recognized event, I'll mention that and speculate based on available data. Alternatively, it might be an acronym in Japanese that I'm not familiar with. Researching recent fights in 2021 would be helpful.