After everyone had gone through the crystal door after helping the Seafolks, Yue became the one to close the door because Kenshiro was busy with Myu in his arms.
As she closed the door and twisted the Knob in the opposite direction, she felt a subtle vibration of Space before large mana was forcibly drawn from her. This startled her as she redrew her hand in fright and started to rethink things.
'My mana... ...If this is the same energy requirement that has to be met when opening and closing a door to an unmarked location, then we have to rethink how many times we have to use this artifact and what situations are disadvantageous to use it.
I'm sure Ken felt it and will be bring it up later, but it absurdly taxing even for me'
Unlike the Gate Key artifact Hagime made which uses Spatial marked places to be able to move from point 'A' to 'B', or most Spatial movement spells that can move someone as far as the eyes can see; this concept artifact forcibly opens a door to wherever or whomever as long as there's a vivid imagination or coordinates of said place or target.
After the first-try surprise passed, Yue then willingly poured mana into the Door Knob as the crystal door became undone and the Knob unstuck.
She looked at it for a moment as if she couldn't believe she had taken part in the creation of such an artifact before storing it in her Storage ring.
"Yue~ What took you so long"
"Nothing... just admiring the closing process of the crystal door."
Shia called Yue out immediately she was seen in the living room where everyone currently sat without alot on their minds.
"Be careful with it, please. it might be our way home "
"It is our way home... it worked fine."
Ken responded to Koari's plea and at that moment, it was Suzu who was the first jumping up and expressing her joy. Lured by that, Ryutarou raised a muffled happy roar while making a guts pose.
Nagayama just smiled with so much happiness, he was about to cry.
Shizuku and Kaori hugged each other with a wide smile. Even Kouki whose expression had been shadowed all this time smiled faintly.
"Thank you Kenshiro, Yue, Hagime. Thank you so much"
After the jumping Suzu was quick to express her gratitude as she began to tear from joy.
"Does that mean I can go home now?--"
"Nagayama! how can you think so selfishly now. What about the others with Aiko-sensei?"
"What? Obviously they would also be able to come. And what did you mean by selfish? Not everyon--"
"Shhhh!!... She finally asleep, she was too energetic. Riveria, can you lead Remia to an empty room?"
Ken quickly stopped conversation between Kouki and Nagayama which was leading to an argument before it could awake Myu whom he put alot of effort into luring to sleep since she had been on edge since the Apostle attack. He then gently gave Remia her child and waited for them to leave the living room before addressing Nagayama.
"To answer Nagayama, yes. We can open a door back home right now but there are certain issues we need to address first.
Don't make that face, there's no major problem that would affect a trip home right now but...--"
"We need an artifact that would shield us from any unwanted summons after we leave right?"
"Yes, that's one issue"
Answered Ken to Hagime's contribution. Shia then voiced her thoughts on the stated issue.
"Are you saying there's a possibility that Ehit can summon us back after all this trouble to create an such a concept artifact?"
"Possibly. We don't really know the full extent of his 'godly' power. It will be really bad if he were to summons us into a trap"
"Tio is right. We are lacking information more than Ehit's forces are dying to know the full extent of my power.
To create a concept artifact to prevent any future unwanted summons will need a different method than what we tried with the Golden Door Knob.
I don't think we can build up enough of such desire unless... unless all of us from Earth, and I mean everyone of our classmates do it together"
"So we have to fetch everyone inorder to be fully ready to go home?"
"Right, everyone must be present... you just reminded me, Ryutarou. Yue did you notice anything while closing the crystal door?"
"...I did actually and I was sure you'd speak of it."
"You should know I'm not a perfect rounded person, right?"
"I guess. Well the artifact absorbed a large amount of my mana when I was closing it and I'm sure it was the same when you opened it, right"
"True, it was very taxing on my reserves but I guess it is to be expected from such a level of conceptualization and the crude methods we took in creating it"
Confused has to why this was a problem in the subject of them going home, Suzu voiced her doubts as Shia backs her up.
"I don't get it. How bad is what you're saying "
"Yeah~ All we have to do is get everyone here then open a door to your world, right?"
"Yes and no. The mana requirements is so bad that either I, Yue, Hagime or even Tio will be lightheaded from mana exhaustion just by opening and closing the crystal door. Meaning it's at worse death for you guys."
"I get what Master is saying. He is saying we have to be mindful of the situation during which we use the artifact and among the heroes only Kouki might be able to open and close the door.
So right now we need everyone around for a single trip, if we don't want Ehit's interruption."
"So all we can do is go out and gather everybody including the inmates in your prison and go home basically, but... I don't want to be an alarm... but what about Ehit.
I'm sure Shia and Tio will be worried leaving their people behind, when he's alive and playing with lives"
What Hagime said got everyone thinking including Ken who had been frustrated by this problem. On one hand, a way home was readily available and on the other he can't just leave with the relatives of his women living in a world controlled by Ehit.
"There's nothing we can do about him since we don't know where he stays and stuff like that... all we can do is to decimate any and all his forces we come across to delay his plans or force him out to analyze his 'godly' powers
After all a self proclaimed god such as himself should have a huge sense of pride and superiority complex to wipe out us 'mortals' by himself when he's surrounded by incompetent people "
Said Ken to what looked like a plan but was actually something to reassure his women that he still planned to kill Ehit even with a way home guaranteed.
....