Sorry for not uploading a chapter, but I didn't have time to translate the chapters into English. Also, if you find any errors, you can let me know and I will correct them.
"Speaking normally"
(Thoughts)
Previously:
The door opens, and the small green-haired girl loudly says
"I'm home!" said the younger green-haired girl loudly.
"Alright, wash your hands and..." The older green-haired girl leans her head out from a door to talk to Izumi, but upon seeing Rimuru, she falls silent and asks, "Is he a friend of yours?"
"Yes, his name is Rimuru Tempest," Izumi said happily.
"Nice to meet you, my name is Inko Midoriya," Inko said happily, pleased that Izumi had a friend.
"Likewise," Rimuru said.
"Anyway, Mom, I'd like to ask you a favor," Izumi said, looking at her mother.
"What favor?" the older green-haired girl asked, confused.
"You see, Rimuru doesn't remember much and only recalls basic information about himself. I would like him to stay here and live with us," Izumi said, looking at her mother.
"But his parents will be worried, besides..." Inko said before being interrupted by Rimuru.
"They can't be worried, at least not now," Rimuru said in a low voice, which the two of them heard.
"No? Why not?" Inko asked.
"You see, Mom, he told me that the only things he remembers are basic information like his name, quirk, birthday, and a little more. He also remembers that his parents are dead," Izumi said sadly. "That's why he's the only person who, knowing that I'm quirkless, supports me and doesn't treat me like everyone else does... so sniff let him stay here sniff please."
"Alright," she said with a false smile that only Rimuru noticed.
(What kind of mother am I, that day...) remembering the day Izumi was crying while pointing at a computer with a video of All Might (That day I didn't support her, and he supported her even knowing she was quirkless.)
"Do you have a spare room?" Rimuru asked calmly.
"Yes, this way," Inko said, heading to the room.
But upon opening the door, she saw various things fall because they were put there since they didn't serve any purpose or weren't used much.
"That's right, we put all the useless stuff in there," she said, sighing before deciding, "Alright, I'll clean the room, and while it's in this state, you'll have to sleep with Izumi. I hope you don't mind."
"Don't worry, Miss Midoriya, as long as I can sleep somewhere comfortable, it's fine," Rimuru said.
"Please, just call me Inko," she said.
"Alright, thanks, Inko," Rimuru said, smiling at her.
TimeSkip: At night
When Rimuru and Izumi were going to sleep, Izumi looked at Rimuru and started to speak.
"Hey, Rimuru," she said, getting his attention.
"Yes?" he responded calmly.
"Promise me that if my quirk doesn't awaken before I enter UA, you'll give me that ability you mentioned," she said, looking at Rimuru while holding out her pinky finger.
"Promise," Rimuru said, smiling as he hooked his pinky with Izumi's, making her smile.
"Thank you," Izumi said, and they both went to sleep.
TimeSkip: 10 years later
POV Rimuru
After that day, if I wasn't a slime, I couldn't have slept. I tried to "sleep" with my back to Izumi, but she suddenly hugged me from behind, so I decided to enter sleep mode, which allowed me to "sleep" peacefully without nerves. Additionally, Inko decided to adopt me, and Izumi became my sister, making Inko my mother. She also enrolled me in the same school as Izumi, and I always defended Izumi from Kacchan or anyone who bullied her, though I couldn't always be there to protect her, so Kacchan took advantage of those moments. School was very easy because I had Yunyun, who memorized everything after hearing it once and told me during exams or homework. She also became more human-like in her speech. If you put Yunyun in a clone of Izumi and had them both talk, no one would know who was Yunyun and who was Izumi. Today is the day when it will be decided if All Might will train Izumi to have OFA or not. I can say these years have been much better than I thought. I'm also doubting whether to tell Izumi about my previous life and death because I don't know how she will react if I do.
End POV Rimuru
We see the slime and the broccoli at the station, where a battle between heroes and a giant shark-man villain is taking place.
"Wow, this villain is huge," Izumi said excitedly.
"Who's fighting?" Rimuru asked, disinterestedly since he already knew.
"At least show some more excitement," Izumi said, pouting as she looked at Rimuru.
"Villain, you used your quirk for malicious purposes when people are going to work and committed a robbery, you are the embodiment of evil," said a tree-man hero.
"It's Kamui Woods! He's a talented young hero gaining huge popularity," Izumi said excitedly.
"Hey, you know a lot about him. Are you a fan?" asked a man.
"No, it's just that my sister is a nerd when it comes to heroes," Rimuru said, smiling.
"Idiot," she said, looking away with a blush, receiving a confused look from Rimuru.
"This is your punishment," Kamui said.
"Show us some of your moves, tree-man," said the man who had spoken to Izumi and Rimuru.
"Eh? Here's the famous lacquered chain prison," Izumi said excitedly.
"Lacquered Chain Prison," Kamui said, launching his attack but being interrupted.
"Canyon Cannon," said a giant woman, kicking the villain.
"I just started today. They call me Mount Lady, nice to meet you," Mt. Lady said in a provocative pose.
Izumi quickly turned to look at Rimuru and saw that he was on his phone. He glanced at Mt. Lady and then back to his phone, giving her great internal relief that Rimuru wasn't "that" kind of person.
"We should go, sister," Rimuru said, looking at Izumi.
"Yes," Izumi said.
"Hey, do you plan to be heroes? It's good to continue and give it your all," the man said, looking at the siblings.
"Yes, I'll do my best / Thanks," Izumi / Rimuru said, smiling.
TimeSkip: Classes
"Okay, all of you are third-year students now. In other words, it's now or never to think about your future, and I'm going to hand out the career aspiration forms," the teacher said, holding some papers.
"Who am I kidding, all of you want to be heroes, right? Since all of you here have good quirks. I warn you that using your quirks outside of this place is against the rules," the teacher said, throwing the papers and warning the students.
"Teacher, don't compare me with these extras," said Bakugo, also known as Kacchan by the broccoli and the slime.
"I don't want to be friends with these guys who have weak quirks. You know?" Bakugo said arrogantly.
"What do you mean by that, Katsuki?" all the students said except for Izumi, who remained calm as she knew that if her quirk didn't awaken this year, Rimuru would give her an ability, and Rimuru, who was "sleeping" at his desk, as he woke up when they bothered Izumi or classes ended.
"Oh, that's right, Bakugo, you want to go to UA High, right?" the teacher said, freezing everyone except for a certain sleeping slime and a certain broccoli.
"That national high school? You need a total score of 79 to get in this year," a student said.
"No wonder extras like you give up. I got an A on the exams, I'm the one going to UA," Bakugo said, standing on a desk, alerting Izumi as she recognized the voice.
"And I got an S," a voice said, making Bakugo furious.
"Who said that?" Bakugo shouted.
"Me. Got a problem with that, Kacchan?" Rimuru said, the last part mockingly, making Bakugo even angrier.
End of the chapter