Persona Q: Shadow of the Labyrinth - Roundabout  

ペルソナQ シャドウ オブ ザ ラビリンス -Roundabout-

On the final day of Yasogami High's cultural festival, Persona 4's heroes notice an unusual bell tower on school grounds. Meanwhile, Persona 3's group hears the same sound and gets pulled into a future where they encounter the Persona 4 cast. Both teams are trapped in the shadow-covered school, but meet two individuals named Zen and Rei who have lost their memories. It turns out that these characters may hold the solution to the mystery behind the sudden appearance of the bell tower.