This is the Japanese webnovel link
Original title:異世界魔法は遅れてる
Romaji title:Isekai Mahou ha Okureteru!
Author:Gamei Hitsuji(樋辻臥命)
Illustrator:himesuz
Publisher:Overlap Bunko
Publication status:Three volumes,ongoing
Before you ask, I know what you want to ask:
Is the MC OP?
Is there a harem?
Spoiler for Summary up to chapter 15:
The MC gets summoned with two other people from Japan, a guy and a girl. They are all friends with each other. The silver haired girl is the court magician who performed the summoning.Turns out there's a mistake in the summoning because only one person is supposed to be summoned. The one who is supposed to be summoned would be granted extraordinary strength and magic abilities. As it turned out, the MC's male friend is the hero. Only the hero is given extra powers.The three are greeted by the princess of the realm and the court magician and were take to the king. First thing the MC told the king was that he has no intention of fighting for him and that all he wants to do is leave. The hero on the other hand, who is a bit like Kouki from Arifureta,accepts. The hero tells the king that on earth, there's no such thing as magic, not knowing that his friend is actually a magician.The girl also accepts because she likes the hero(she's part of his harem).Because the king is a kind and wise ruler(unlike the scumbag kings from other series), he understands the MC's feelings and treats him as a guest. As it turned out, the King was against the summoning of a hero from another world since he didn't want to forcibly drag individuals into their world's fights. He was overruled by rulers of other countries and was forced to summon a hero. The court magician girl trains the hero and the other girl in magic while the MC stayed in his room,apparently unwilling to get out. Apart from the King and his friends, everyone in the castle thought that he's a coward who lost his wits because he's summoned to an unfamiliar land.In reality, the MC slips out of his room occasionally and studied about the world in the royal library. On some occasions, he even broke into the castle's forbidden libraries. The court magician,already suspecting that he's a magician tails him. She even sets up a trap for the MC,setting up an automaton golem that could have potentially killed the MC if his magic isn't much more advanced than this world's. She later reports to the King about her suspicions but the King decides not to interfere with the MC's activities. He instructs her not to do anything to the MC. He suspects that the Court Magician will still try and harm the MC but thought that it wouldn't be serious and that he would punish her afterwards. The MC fights the Court Magician and he totally had her owned. Even though the Court Magician is regarded as a genius, she lost because the world's magic was way too inferior. As a condition not to be killed by the MC, he forces her to sign a contract where she will die if she told anyone,especially his friends, about his true identity. Since the King already knows that the MC is a magician,he found it odd that the Court Magician was unwilling to report anything on the MC. He quickly deduced that the Court Magician was under some form of duress not to tell him anything. Nonetheless, he deduced the full story by having the Court Magician,Ferumenia Stingray,remain silent when he deduced correctly and shook her head when he didn't. He summoned the MC and had a frank talk with him.The MC tells him about how in the real world, magic users are nearly extinct due to the threat of extermination.He also tells the king that he doesn't want his friends to know that he's a magician because those who knows about it are often killed.This is because numerous people wants to keep magic a secret in the real world. The MC also tells the king that he has an idea about how to return to earth. He plans to bring his friends back with him when they've finished their hero activities. When asked about why he doesn't help the hero if he's so OP,the MC tells the king and Ferumenia that he doesn't think that either the hero or himself can beat the demonic armies who has an army of at least one million soldiers. He thinks that no matter how powerful they are, they will ultimately be overcome by numbers. Nonetheless, he doesn't stop the hero from fighting the demons because he believes that his friend isn't the sort of person to die easily. Ferumenia gets demoted as punishment for disobeying the king.The king supports the MC's actions and the MC parts way with the hero and the girl on the day the hero also departs to begin his campaign against the demons.He plans to travel to the neighboring empire but before that, he has to join a guild, since joining an adventure's guild gives him benefits such as lodging and identification. The king gives him twenty gold pieces before he leaves. When he shows up at the guild, he meets the red haired girl from the second cover. She received a divine revelation that instructs her to exchange names with people she met. The guild refuses to admit the MC because he's dressed in a tuxedo and he doesn't carry any weapons or a mages' staff.They thought that he was joking around with them. One of the guild members challenged him to a fight and was owned badly. The guild admitted him when they say how OP he is. To assess his ranking,the guild arrange him to have a duel with two powerful senior members and they too get owned.
By the way, this series is also getting a drama CD.The VAs are:
Nobuhiko Okamoto for the MC
Satoshi Hino for the Hero
Ayane Sakura for the female friend
Marina Inoue for Ferumenia