After sending out memory crystals to all people related to those 24 million criminals, Aleron separated them, keeping 3.3 million black ones for Xorg transformation, and sending the rest who were red ones into Hell for another chance at life, depending on their nature.
When he was done with that, he finally shut his eyes in his bedroom and fell asleep soundly.
Rias had nothing more to do after that, so she also returned to the secret realm using the ring Aleron gave her.
Seeing him sleeping soundly on the bed, Rias kissed him.
"Get plenty of rest and sweet dreams," Rias softly giggled looking at Aleron's sleeping face.
Afterward, she left with Roxen towards the Crystal Spires of Auroraville where others were training.
But when she arrived there, the atmosphere sensed was heavy and suffocating.
Everyone didn't speak at all, and just purely focused on their training loop.
Kill crystal monsters.
Get their elemental crystals.