A perfect all-kill happens when a song is #1 on all major real-time and daily charts, as well as instiz's realtime iChart and Weekly iChart. With a new week, all of that happened and IU has achieved another perfect all-kill!
Congratulations IU! Eight of her tracks are still in the top 10 of the instiz chart. It's hard enough for most artists to get one perfect all-kill in their entire career but IU has done it for three tracks in under one month.