I Attained Invincibility In The Real World - Chapter 723 - 393 Investigation and Requesting Help

Three Days of Happiness is a novel by Sugaru Miaki, also known as Fafoo. It’s a rewritten version of the story originally posted to 2ch.

The premise of the story revolves around a shop where one can sell away the remaining years of their life, and the consequences of doing so.

“I Say A Little Prayer” is a short related story which was posted along with the novel’s release. It spoils some things about the main story, but nothing major.

Kakashi has lived a sheltered life within the protective confines of a barrier, which shielded them from the dangers that lurk outside. Raised by his devoted mother, Ako, and loving sister, Tokah, he only know a world of happiness and joy. Living in a world where he thought nothing could go wrong.But when a group of men invades their home, everything changes. In the brutal assault, Kakashi witnesses his mother's tragic death, a moment that shatters his naive understanding of safety. While his sister manages to escape, Kakashi is captured and subjected to experiments designed to exploit his hidden powers.Years later, amidst the ruins of a collapsing facility, granting Kakashi a chance at freedom. Rescued by an academy dedicated to training gifted individuals, he discovers not only the extent of his abilities but also the resolve to seek vengeance against those who tore his family apart.Driven by the desire to reunite with Tokah and avenge his mother's murder, Kakashi embarks on a journey filled with action and self-discovery.As he navigates the treacherous underbelly of a world rife with superhuman conflicts, he must confront his own problems while mastering the very powers that once made him a target.

Shion, the ‘Hero of Darkness’. He was said to be the strongest hero ever. He believed one thing, and that was his current party members.

“I’ll defeat the Demon Lord with this party!”

That is what he swore to do, but a tragedy occurs. He was painfully betrayed by the girls that he trusted.

He barely held onto his life, but the incident left a deep scar in his heart.

He gave up on living, and while he was wandering around in a forest, looking for a way to die, a single monster appeared in front of him.

“Will you kill me, please?”

The monster asked Shion, who was still strong, despite losing his powers.

What Shion, who wanted to die as well, did was―

On the surface, he is the aloof and standoffish patriot whose sole purpose is to serve the nation. On the darker side, he is an invincible, powerful and mysterious man.