Looks like the wig was for a short drama that is up for voting to become a regular show in September.
Between 10 different short dramas, starting from April, 2 of those dramas are pitted against one another and viewers vote for the one they want. And then in September, the 5 dramas that won their 'battles' will put up to vote once more to determine which one will become a regular show. The drama that Yuka appeared in was put up to vote in June and ended up getting 74.7% of the votes for the month (the biggest vote percentage so far)!
The first episode is
here at H!O in 1280x720 XviD
or you can all 3
here at the official site.