Perfected Ai Kotoba on Extreme.
When I started the song, I felt it was a bit too easy for an Extreme song. Well, the Extreme bit is this:
Luckily, this occurs early and only once in the whole song, and you actually just have to press circle-X-square-triangle buttons in that order repeatedly.
The rest is smooth sail. I took 3 tries: the 1st was for the aforementioned shocking discovery, the 2nd was scouting for more possible surprises, and third, execution. And I used 5 help item chances on my last try, my thumb got too trigger-happy after the previous song magnet :p