After suffering repeated setbacks in life due to his severe social anxiety and reclusive nature, middle-aged man Toudesuke Saionji pours all his energy into his hobby of inventing. One day, an experiment goes wrong and causes a massive explosion that kills him, sending him reincarnated into a fantasy world. Stranded with no way back to his original world, Toudesuke simply wants to live a quiet, peaceful life dedicated to his inventions, avoiding attention and conflict.

However, his plans for a low-key existence are complicated when he meets Satalia, a vampire girl who becomes deeply attached to him. She follows him loyally, and together they try to find a secluded place where Toudesuke can work on his creations without interference. Their search for a tranquil home repeatedly goes awry, as various troubles and encounters draw them into adventures they never intended to have.

Along the way, the pair gain a new companion in Garlic-chan, a character who joins their journey. The story follows Toudesuke, Satalia, and their growing circle as they head toward Yamadaikan, the largest city in the kingdom of Mizeriya, still hoping to finally find a place where they can settle down and live in peace. The narrative blends fantasy adventure, slice-of-life moments, and comedic situations that arise from Toudesuke's introverted personality and his inventions, all while he quietly becomes more entangled in the world around him than he ever wanted.