In Which A Shut-In Boy is Reincarnated as a Goblin

In Which A Shut-In Boy is Reincarnated as a Goblin (Japanese: 引きこもり少年がゴブリンに転生する話 Hepburn: Hikikomori Shonen Ga Goburin Ni Tensei Suru Hanashi), often shortened to GobuTensei (ゴブ転生), is a Japanese light novel series written by Nowa and illustrated by Burojin. The story focuses on the exploits of an unnamed teenage shut-in who is killed by accident by a drunken man, reincarnating into a fantasy world that works similarly to the RPGs he played in his previous life. However, upon discovering he has been reincarnated as a goblin, the boy quickly realizes that he is not the hero of this story.

The series, like many light novels, was originally published on the user generated website Shōsetsuka ni Narō from 2013 to 2017 before being picked up by Shufunotomo, who published the first volume of the light novel in 2015. A manga adaption of the light novel was published by Square Enix as part of their Monthly GFantasy magazine, illustrated by Ken Tanaka. Both the light novel and manga have been licensed in North America by Yen Press, who translated the first volume of the light novel in 2016. The manga has been adapted into an anime series, which was animated by Eight Bit. The series ran for four seasons, running from June of 2018 to August of 2025. An anime film based on the series premiered in September of 2023, as well as there being five OVAs based on the series. All of these works were translated into English by Funimation and were released as an exclusive to Crunchyroll in foreign countries.

Plot
The story follows a teenage shut-in, who spends all of his time playing RPGs and watching fantasy shows. His obsession causes him to constantly fantasize about wanting to be a legendary chosen hero, but he claims to have never been given the chance. While out one night, he confronts a drunken man harrassing a girl, which ends in the man pushing him and accidentally killing him when his head cracks against the road. The boy is quickly reincarnated into the fantasy world of his dreams, but his hopes of being a legendary hero are smashed when he realizes that he is now a weak goblin, ranked at Level 0. As a goblin, the newly renamed "Rioma" is initially depressed with his new life until it's pointed out to him that monsters in this world are looked down upon by others. So much so that a party of low level adventurers feel no shame in picking off entire tribes of goblins for easy XP. Infuriated by this, Rioma retaliates and ends up accidentally killing one of the party members, which brands Rioma with a new mystical item called a Mana Glyph, which allows him to naturally generate and gain mana, something goblins aren't meant to be able to do. With this new power, Rioma decides that his purpose isn't to be the hero of the story, but rather to defend those who aren't, whether they be monster, man, or something else entirely.