It’s been a while since Lucky Star airs on TV and I missed her antics and sarcasm. What we have here is Konata in one of her Lucky Star outfit, her middle school swimsuit.
Since it has been few years the show airs, I couldn’t remember from which episode was it that she wore it. Upon Googling, I found out on wiki that she wore this swimsuit in Lucky Star’s episode 6 “Fixtures of Summer”.
In that episode Kagami, Konata, Tsukasa, Miyuki, Nanako and Yui take a summer trip to the Miura-kaigan beach area. It’s the episode where Yui did her Initial D parody.
Chibi Konata here is made by Ledah.