Noir Stargazer, son of a "beggar noble", is down on his luck after his application to become a librarian is rejected when a higher noble swiped the position for himself. Left with little recourse, he has no choice but apply to be a mere adventurer. Fortunately, in a world where every human being is gifted with unique skills, he uses his ability to mentally consult the Great Sage to help him advance up the ranks of society.
One day, the Sage directs Noir to a hidden dungeon which so happens to be the abode of Olivia Servant, a legendary heroine imprisoned and slumbering within its depths for centuries. While he cannot free her, Olivia telepathically bestows upon him her signature skills, which allow him to create, edit and bestow skills of his own, at the cost of his own life force. This amount can be replenished by satisfying desires, be it indulging in a hearty meal, attaining great wealth... or making out with pretty girls, such as Emma Brightness, his childhood friend, Lola Meltrose, a receptionist at the local adventurers' guild, and Luna Heela, an elven priestess.
The Hidden Dungeon Only I Can Enter ~Secretly Becoming World Strongest~ (俺だけ入れる隠しダンジョン 〜こっそり鍛えて世界最強〜, Ore Dake Haireru Kakushi Dungeon ~Kossori Kitaete Sekai Saikyō~) is an ongoing 2017 web novel series written by Meguru Seto, published on the Shōsetsuka ni Narō site, with a near-concurrent light novel version illustrated by Note Takehana and published by Kodansha under its Lanove Books imprint. It has also received a manga adaptation illustrated by Tomoyuki Hino and also published by Kodansha under its Suiyōbi no Sirius imprint, as well as an anime adaptation directed by Kenta Ōnishi for Okuruto Noboru studio which started airing on January 9, 2021. The novels and the manga adaptation are both licensed in English by Seven Seas Entertainment.
Tropes:
- Adaptational Modesty: In the manga and anime, Olivia wears a simple dress. In the original light-novel, she's completely naked since her clothes rotted away long, long ago.
- Adventure-Friendly World: The world Noir and co. live in is one where there are all kinds of monsters around which adventurers can find constant work for at the local Adventure Guild. Also, there are many, many ancient ruins and lost locales which people call the titular "Hidden Dungeons" that are full of heavy danger but also teeming with rich rewards. Also, if one can handle the exam and steep entry fee, you can also enroll in the Hero Academy, and (as Noir puts it), be "set for life".
- And I Must Scream: Olivia has been chained inside a dungeon, where no one can see or hear her, for two centuries, and any attempts to free her would kill her. She's ecstatic when Noir chances upon her, and treats her kindly, rather than try to exploit her in any way.
- Aristocrats Are Evil: With the exception of the main characters and their immediate families, the aristocrats are all entitled twits who preen around based entirely on the merits of previous members of their bloodlines, or use money to skate past any obstacle they can. Noir even lost his job as a librarian in chapter 1 to some unnnamed higher tier noble, who bribed the interviewer just to deny him the position. In later chapters, this starts to fade as Noir racks up heroic accomplishments, and the nobles realize it's a good idea to be on good terms with a powerful and promising adventurer, regardless of social status.
- Battle Harem: Noir's harem predominantly also accompanies him on quests for the adventurer's guild and can hold their own in a fight, thank you very much.
- Big Brother Attraction: Though Noir completely deludes himself otherwise, his younger sister Alice is very interested in a relationship with him that involves erotic acts.
- Blessed with Suck:
- Noir starts the story only with a "Sage" ability that allows him knowledge beyond any mortal, even using it to find the titular Hidden Dungeon, but the drawback is a massive, crippling migraine that won't go away until Emma comes along and kisses him on the lips.
- Olivia is somehow able to live over a century without need for food, water, or having to worry about her "ahem" biological functions, but she's chained to the wall of a dungeon, unable to leave without dying.
- Blue Blood: Starting from the bottom, the titles of nobility are: Baronet —> Baron —> Viscount —> Count —> Marquis —> Duke. Downplayed with baronets (like the Stargazers) who are still scorned by other nobles.
- Cast from Lifespan: How curse-breaking magic works. Luna and her mother were born with the ability to break curses, and to do so, they have to sacrifice a portion of their life-span: the stronger the curse, the greater the cost.
- It's implied that Luna has already significantly shortened her lifespan through this before Noir changed her ability. Though being a half-elf she can still expect to live for a long time.
- Cast from Money: Both Noir and Luna eventually get their special abilities to work this way, should they wish. Noir changes Luna's curse-breaking cost from lifespan to money so she can break curses without it killing her, and Noir crafts a skill to allow him to acquire LP for gold, though he prefers to get LP from the loving of his Rescue Romance harem.
- Casual Kink: Noir has gained LP from being on the "M" side of some S&M play on several occasions, namely being sat and stepped on.
- Childhood Friend Romance: Noir and Emma have been friends since childhood, and they see nothing wrong with kissing each other on the lips, or doing other "couples only" things.
- Fair-Weather Friend: On several occasions, Noir gets the cold shoulder from some higher-ranked noble because he's from a poorer "upstart fake noble" baronet family. When some even higher ranked noble comes along and gets friendly with Noir, suddenly the dismissive noble decides to show Noir decency. Noir doesn't play along.
- Freeze-Frame Bonus: Noir's Discerning Eye often picks up on subtle-yet-important details that may go unnoticed because Noir himself doesn't draw attention to them and the screen doesn't linger on them for long. For example, when first meeting Luna, Discerning Eye briefly shows that she has the skill "Cowardice", which doesn't come into play until much later in the same episode.
- Harem-Powered: Noir's special abilities frequently pave the way for erotic acts. His innate skill to consult the Great Sage leaves him with a crippling headache that is quelled by kissing, which Emma is keen to offer. The three skills he gained from Olivia require LP, which is replenished by, among other things, engaging in erotic acts with members of the opposite sex. There is a very quick "rate of diminishing returns" when playing around with the same girl over and over again, as such Noir, and Olivia, the one who granted him this power, need a harem to make the most of it. Emma is resigned to it, but does not like it.
- Intimate Healing: Noir gets a serious headache every time he queries the Great Sage, which goes away when he and Emma kiss.
- Killer Rabbit: Parodied. One of the first monsters Noir and Emma are sent to hunt down is a rabbit, but what makes it dangerous is that it has the size, strength, and temperament of a bear, without losing any of a rabbit's speed or agility. What's worse is that said rabbit also has a horn on its head to make its charges even more lethal.
- Laser-Guided Karma: Noir is invited by his peers to go peep inside the girls’ section of the hot spring. He simply refuses and actually helps to round them all up. In return, Noir becomes the only male permitted (though blindfolded) to join their bath.
- Male Gaze: The anime has no problem showing off close-ups of female characters' large busts and other intimate parts.
- Mate or Die: Though it hasn't gotten that far, yet, if Noir's LP ever reaches 0, he's dead, so he must engage in erotic acts with all the girls of his harem, and a few outside it, to continue to use his skills without burning away all his life force.
- No Antagonist: The conflict in the story is Noir vs "society" or vs "The world" as a Coming of Age Story. He almost never has someone coming after him, specifically, or deliberately getting in his way, at least not for very long.
- Pass the Popcorn: The first time Emma and Lola fight over Noir, the rest of the Odin guild gathers to watch and cheer on the "lover's quarrel".
- Powers as Programs: Noir can write and edit his own skills, give them to others, and alter other people’s skills just as if they were programs.
- Rescue Romance: Luna and Maria are in Noir's harem because he's directly responsible for saving their lives, and they're grateful.
- RPG Mechanics 'Verse: Every adventurer has a set of "skills" available to them, and these skills have quantifiable ranks that can be improved. Noir’s skill-editing skills come with pop-up text boxes, and he can see numeric stats like his LP.
- Spell My Name With An S: The names of the characters change between mediums. For example, Noir's family name changes from Stalgia in the novel to Stargazer in the manga.
- Supporting Harem: Noir and Emma are clearly the leading love interests, but the other girls of the harem give Emma serious competition.
- Standard Hero Reward:
- For removing Maria's curse, her parents allow Noir to romance her, and on top of that, present him with a HUGE amount of money for "treatment fees".
- After Noir stops the boys in his class from peeping in the hot springs (using up 4300 LP to do so), he gets hugs from the girls, gets to bathe with them too, albeit blindfolded, and gets Marshmallow Hell from Emma and Elna. The resulting stimulation nets him over 10,000 LP.
- Top Wife: Emma jealously guards her position as Noir's primary love interest.
- Wins by Doing Absolutely Nothing: In some side materials, the other male students take advantage of Noir being unavailable for some reason or another to perv on the female students. This infuriates the female students and makes them more appreciative of Noir who doesn't do this sort of thing without their consent to his complete bafflement as he has no context for why his reputation went up.
- World of Buxom: Many of the women, Noir's harem especially, are capable fighters and well-endowed to varying extents.
- Your Days Are Numbered: The curse, "sixteenth death" kills whoever is afflicted on their sixteenth birthday if not broken. Maria is introduced to the story having this curse, with her "sweet 16" birthday just a week away.
