The preparations were really just Lith trying to inform his wives of his long leave and amassing some survival essentials from the treasury.
He called his wives and lovers while on his way to the treasury with Luna and got himself a few important things that he felt would be useful later on.
It took him roughly ten minutes to do so and once finished, rushed back to the portal.
Zen was still staring at the portal, but was now showing signs of struggle and could pass out any moment.
Lith walked up to Lilith and kissed her softly. "I'll be back soon."
Lilith smiled and hugged him. While patting his back, she said, "Be sure to not fool around much and focus on self-improvement."
"Hmm?" Lith didn't understand what his mother said, but nodded nonetheless and broke the hug.
He then walked up to Sylvia and said while looking at Zen, "Take good care of him and get him in touch with Ren."
Sylvia bowed slightly. "As His Highness commands."