K-ON! - 1x12 - 軽音！- Followmy.tv

Yui is still sick from her cold, which is possibly attributed to her wearing a short yukata for too long. As the band tries to make do with Azusa as lead guitarist, Yui supposedly shows up over with her cold. However, her playing is too perfect and a slip of the tongue reveals that she is actually Ui, who had managed to play after a few days practice. Yui appears, but is still in no condition to play, so Mio suggests that she stay home until the day of the live performance. Yui eventually makes it in time, but forgets her guitar at home, so Sawako fills in for her while she goes to get it. Yui returns in time for the second song and the performance goes well, and the band even does an encore.