As shown in the manga Chapters 27 and 28, Momoka arrived at the Borderland with Asahi and were immediately escorted by the local chief dealer to the observation center which is kept secret from the players. The 2 girls were briefed with the rules of dealers and their relationship with the players, including that a player's victory means the death of the dealer of that game. In the dealers' center, Momoka heard of a rumor about leaving the Borderland after the dealer has successfully caused 100 players' death, which was never verified.
Disgusted by the other dealers' corrupted mind to pray for their players' death, Momoka volunteered to participate in an extreme game setup in the Beach society which requires 1 dealer to commit suicide and another dealer to help preparation. Momoka wished that succeeding her last mission would stack their accumulated players' death to 100, so that would allow Asahi to return to the original world. On the other hand, Momoka wanted the players could calmly see through the trick of the game because she was fed up by the dealer-player massacre and everyone losing their humanity in the Borderland.