In Roy's opinion, Lilith's current situation was probably similar to his. After returning from the Void, she was also alone. If she wanted to take revenge on the Burning Hells, she had to have at least a sufficient number of troops.
Unlike Roy, Lilith couldn't summon demons from the Abyss. She had been away from the Abyss for too long. Even if she could summon some demons in the name of a demon king, the numbers might not be enough to meet her needs.
After thinking about it, he felt that she could only rely on her children, the nephalem.
However, it was not easy to form a nephalem army. Thanks to the repeated invasions of the seven demon kings and the Burning Hells, the nephalem had always been vigilant against demons. Roy put himself in Lilith's shoes and imagined it. He felt that if she wanted to raise an army that belonged to her to fight against Hell, then the best entry point should be royal authority!