Breaking a promise

Chapter 40: Crisis

She was crying.
Crying very hard.
Eri was sitting next to Mirio; he was lying on the floor unconscious and partially hidden. As Akane , Mr.Aizawa and Midoriya entered the room, Recovery Girl was already by his side.
"Mirio! What happened?" Midoriya asked anxiously.
"W-w-we were just working on my quirk and then he just fell over!" Eri cried.
"He's not responding completely to my attempts to wake him," Recovery girl replied.
"I'm sorry Deku!"
"It's alright Eri, it wasn't your fault."
"Y-yes it is! I touched him and my quirk started working and he fell down!"
"Akane, can you see if Mirio's quirk is working right?" Mr. Aizawa asked.
"I don't know; if he is currently permeable then I can't touch him. You'll need to stop it."
"I can't while part of his body is in the floor; if I did parts of him would get sliced off."
Midoriya was thinking frantically, trying to figure out how to get around the permeation quirk. There was only one solution.
"We gotta break the floor around him!"
"Ugh!" Mr. Aizawa groaned in regret.
Without thinking Midoriya activated one for all and started smashing the floor panels that Mirio was immersed in. Eri stood behind the others with tears still streaming down her face.
Meanwhile Mr. Aizawa quickly activated Erasure and the unconscious teen became touchable again.
Akane laid her hand on his left shoulder. A bright green flash erupted from his eyes and mouth as his body flexed upwards.
"This is odd," she said.
"What is it?" Recovery girl asked.
"It's like his quirk is out of his control. I am not sure right now why it is acting this way."
"If he doesn't get enough oxygen back into his system then he risks brain damage or worse." Recovery girl noted.
"Can you tune it like you did with Eri?" Midoriya asked.
"You mean so that he can control it? I can try."
Another bright flash.
"Mirio! How do you feel?"
There was no response apart from muscle twitches. Recovery girl sighed.
"He probably needs more medical attention now."
"Akane, what did you do?" Mr. Aizawa asked.
"I had no choice but to take it offline. He still doesn't have control but it won't activate until further changes are made."
Eri was still visibly upset.
"It's alright Eri; what you did had nothing to do with it," Mr. Aizawa said softly to her.
Midoriya was in shock; it seemed like Mirio had been back to his original self over a month ago. Now it seemed like a challenge had reared its head for the worst.
To him, it seemed like his quirk was activating on its own. And since Mirio couldn't hold his breath while permeable, it was only a matter of time until he passed out. Now all that could be done was to revive the solid Lemillion.
"Ugh...."
"Mirio!" Everyone said.
".....what.... is going on? Where's Eri?"
"I'm over here," she replied.
He yawned and slowly sat upright to everyone's surprise.
"How long was I out for?"
"A long time ." Eri said.
Recovery girl continued to nurse him back to health while Mr. Aizawa proceeded to send Midoriya and Akane back to the dorms but not without saying goodbye to Eri and Mirio.