Alternative Titles
English: An Evil Dragon That Was Sealed Away for 300 Years Became My Friend (Pre-Serialization)
Japanese: 300年封印されし邪龍ちゃんと友達になりました

Information
Type: Manga
Volumes: 1
Chapters: 13
Status: Completed
Published: 2019
Genres: Comedy, Fantasy, Slice of Life, Monster Girls
Authors: Yaki Tomato
Serialization: N/A

Synopsis
Youta wanted a friend, so obviously, he magically summoned one.
He didn’t quite count with the fact that he’d summon Mumu, a mighty and evil dragon girl, notwithstanding that due to hundreds of years of imprisonment, she’s very needy, very weepy, very clingy, and lonelier than the button “9” on a microwave oven.