I've Been Killing Slimes for 300 Years and Maxed Out My Level

Alternate Titles

スライム倒して300年、知らないうちにレベルMAXになってました
Slime Taoshite 300-nen, Shiranai Uchi ni Level Max ni Nattemashita

Synopsis

Azusa Aizawa is an extremely ordinary office worker who dies of overwork at the age of 27 only to be reincarnated into another world as an immortal witch. Reflecting on her previous life, she begins living a leisurely and slow life in the remote highlands. In her day to day, she earns coins by slaying slimes, makes potions like a witch, takes care of the village at the foot of the mountains, or simply enjoys doing nothing at all. Her life continues like this and she becomes known as the “Witch of the Highlands."

After 300 years, due to all the experience she has accumulated killing slimes she reaches level 99 and becomes the strongest person in the world. As rumors spread, her life begins to get livelier as not just adventurers confident in their skills but also dragon girls begin appearing and challenging her to fight. And even mysterious monster girls show up calling her “Mom”!

Background

I've Been Killing Slimes for 300 Years and Maxed Out My Level began as a light novel series written by Kisetsu Morita and illustrated by Benio that began in 2016 on the user-generated novel publishing site Shosetsuka ni Naro and was picked up the next year by SB Creative who has been publishing it under their GA Novel imprint. It has been licensed in North America by Yen Press. There have been several spin-offs to date including I Was a Bottom-Tier Bureaucrat for 1,500 Years, and the Demon King Made Me a Minister which was published in Gangan Online from July to September 2017, Food for an Elf which was published in Gangan Online and Manga Up! from April to June 2018, Red Dragon Women Academy which was published from July to November 2019, and Red Dragon Women Academy Episode 7 which began in January 2021.

Several manga adaptations have also been published to date including a manga of the main series illustrated by Yusuke Shiba that began serialization in June 2017 and is currently ongoing, I Was a Bottom-Tier Bureaucrat for 1,500 Years, and the Demon King Made Me a Minister which was serialized from January 2019 to August 2020 and released as three tankobon volumes, and Red Dragon Women Academy which was scheduled to begin serialization in summer 2020 but was postponed.

An anime adaptation was announced in October 2019 during the "GA Fes 2019" event. It is being produced by Revoroot and features Nobukage Kimura as director with Tatsuya Takahashi handling series composition, Keisuke Goto handling character designs, and Keiji Inai composing the music. The anime’s opening theme song is “Guda Fuwa Every Day” by Aoi Yuki, and Azumi Waki will be performing the currently unannounced ending theme song. The anime will premiere in Japan on April 10, 2021 on Tokyo MX, BS11, and AT-X, and it will be streamed through Crunchyroll in North America.

Characters

Azusa Aizawa (Voiced by: Aoi Yuki)
The “Witch of the Highlands." She was previously an ordinary office worker who died at the age of 27 due to overwork and was reincarnated into another world as an immortal witch who looks like a 17 year old. She one day discovers that she has defeated so many slimes that she has maxed out her level.

Laika (Voiced by: Kaede Hondo)
A red dragon girl. She was once the strongest monster in the Nanterre Province, where Azusa lives, but she challenged Azusa to a match and lost. Afterward she took on the form of a young girl and became her apprentice. She is serious and hardworking.

Falfa (Voiced by: Sayaka Senbongi)
A slime spirit girl born from the souls of the slimes defeated by Azusa. She is Shalsha’s twin older sister. She sees Azusa as a mother and clings to her. She has an honest and cheerful personality.

Shalsha (Voiced by: Minami Tanaka)
A slime spirit girl born from the souls of the slimes defeated by Azusa. She is Fratorte’s twin younger sister. She spent 50 years training to defeat Azusa but failed. Afterward, like her sister, she began seeing Azusa as a mother and wanting to be near her. She is introverted and quiet.

Halkara (Voiced by: Sayaka Harada)
An elven apothecary girl. She makes a lot of money from the “nutritional sake” she develops but was targeted by Beelzebub and comes to Azusa for help. After a commotion, she becomes her apprentice. She messes up more than anyone else.

Beelzebub (Voiced by: Manami Numakura)
A high-ranking demon girl. She serves as the Agriculture Minister of the Demon Realm. She likes Halkara’s “nutritional sake” and comes to Azusa in search of it. She is belligerent but is also very caring.

Rosalie (Voiced by: Riho Sugiyama)
A ghost girl who died when she was 15 years old.

Fratorte (Voiced by: Azumi Waki)
A blue dragon girl who is over 400 years old.

Music

Opening Theme Song: “Guda Fuwa Every Day” by Aoi Yuki

• Anime Site (Japanese)
• Twitter (Japanese)

• Original Creator: Kisetsu Morita
• Original Character Design: Benio
• Director: Nobukage Kimura
• Series Composition: Tatsuya Takahashi
• Character Design: Keisuke Goto
• Sub-Character Design: Emi Honda
• Art Director: Ken Naito
• Color Design: Satoshi Takezawa
• Director of Photography: Sota Mikami
• Sound Director: Satoshi Motoyama
• Music: Keiji Inai
• Music Production: Nippon Columbia
• Animation Production: Revoroot