Another angle: Sometimes, people use usernames combining their name with other elements. Could Anna LK21 be an influencer or a YouTuber? I don't recall any famous ones by that name. Maybe it's a character from a K-pop group, but again, not that I know of.
Wait, the user wrote "anna lk21" – maybe it's supposed to be "Anna LK21" as in a person's name. But without more context, it's hard to say. If LK21 is a site, maybe the user is referring to a leak or a controversy? For example, if a new Anna's project was leaked on LK21. Alternatively, maybe there's a misunderstanding in the query.
There are two primary films often associated with this title: All About Anna (2005)