A day had passed, and Dante allowed events to unfold as he simply relaxed. He learned, through Morgana, that there would be a school-wide festival - a winter festival not only to celebrate the first semester but also to "Honor the Departed."
Yes, they were organizing a festival to honor the dead from the Dungeon, who, in this case, were very much alive.
In summary, the festival was orchestrated by the rulers' children, who coincidentally suggested a festival at the end of the semester to "mark the evolution of the youth." Quite convenient, isn't it?
Dante viewed it as one thing: celebrating his death.
So, he decided to embrace the event. Since it was to celebrate death, they would celebrate it in grand style.