having JUST finished the game, shes technically in the last couple minutes, but is followed immediately by a "sorry, thats the last content we have currently" splash screen. gotta follow the main "prologue" quest till its done.
have you been progressing everyone to the point of getting the message "no more content" for each girl? cause i think ari is the main one to progress that. its not the event where she tells you about the demon, its the event AFTER that where you meet her
