At first, the Shadow Soul had indeed been extremely cautious and conservative.
She had considered whether the end of the Secret Passage would be blocked by a door or guarded by someone. She had also considered whether anyone inside had set traps or prepared an ambush.
That was why she had specifically used Living Corpse Preservation to conceal herself.
To ensure she had enough mana to deal with unexpected situations, she had sought out Miss Janet, who was happily playing with a client.
As a Blood Mage of the Path of Love, Janet could use her own vitality in place of mana to cast weakened versions of spells. Janet's Path Trait also allowed her to actively link herself to a target, using her own vitality as fuel to bear half of the other party's spellcasting cost.
Forge, the Shadow Soul, and Janet were not teammates who strictly shared one fate, but they were all acquaintances in real life. They had a foundation for cooperation.
Forge was too unyielding and had voluntarily given up on this ritual. The ritual was extremely difficult this time, so the two of them had to cooperate closely.
Although Janet felt that being alive was pretty good, and as an extraordinary being of the Path of Love, she had value for conversion in the eyes of these Children of the Moon, if she performed well, the client should be able to buy her directly.
Even so, she readily agreed to the Shadow Soul's request for cooperation.
Simply put, Janet hid herself in the Shadow Soul's cloak by imitating Living Corpse Preservation, then served as a Blood Pool to bear the Shadow Soul's spellcasting costs, allowing her to store Sequence Arts.
The Petrification Ray used earlier to trigger the Sequence Art had also been cast by Janet