In most ordinary high schools, many stories and rumors float around—some scandalous, some happy and some...more macabre. One such example is of monsters lurking in an abandoned mansion outside of town. Such tales, however, prove too tempting to resist for Hiroshi and his friends Mika, Takeshi, and Takurou. They decide to brave the rumored dangers in order to investigate the manor and complete a test of courage. Each of them approaches the mansion with an overwhelming sense of dread. And when they enter, they come upon a blue monster named Ao Oni who attacks them. As Hiroshi and his friends try to solve the various puzzles in the mansion and escape their new blue nemesis, they find themselves meeting several horrible endings as they fail miserably.
Episodes
Hiroshi and his classmates head to an abandoned mansion on the outskirts of town that's rumored to be the home of a terrifying monster. But the innocent test of their courage goes awry when they find themselves locked in! To keep everyone calm, Hiroshi does a head count. One...two...three...
Terrified by the mysterious blue monster roaming the mansion and lacking the strength to continue running, Takeshi hides in a closet. I can't stop shaking...
Despite being trapped in a creepy mansion with a blue monster, Mika finds that she can endure the stress as long as she's with Takurou. But the one thing she can't endure is the thought of dying without telling him how she feels. I don't want to have any regrets...
Sometimes, guests come to Aooni's home. Aooni loves guests who are refined and genteel. Today is another day of Aooni working as hard as he can to be hospitable to his guests.
The absurd game of tag forced upon the group has driven Takeshi to exhaustion. So, he spends another day in his closet sanctuary. But even the closet isn't safe enough for him to relax. While resting, Takeshi is suddenly engulfed in a mysterious light...
The boys are afraid of what Mika must think of them, after being cooped up in the creepy mansion with the bizarre blue monster. But another day has come and gone, finally, the reason the boys have fought to survive so hard is here: Mika is going to take a shower! “No matter what, I’m going to peek!”
The piano room is home to a locked storeroom door with a mysterious symbol. Takurou and Takeshi are sick of being jerked around by puzzles, but Hiroshi is starting to enjoy figuring them out. There’s no puzzle he can’t solve...this is a game, after all.
The weird blue monster is crying! Sensing an opportunity, Takurou moves to help him out, believing it will save his own life. “I found this earlier. I think it’s just what you need...”
Local city mascots aren’t just in vogue now, they’re a full-fledged subculture. One day, Fuwatty sees a local mascot on TV and thinks, “Why not me?”
The mansion houses countless contraptions and numerous deathtraps. Regardless, Takurou never hesitates to hit a button or push a level. “If you don’t move forward at all times, nothing will change.” Even when things suddenly get, really, really bad...
Takeshi hasn’t gotten a single moment’s rest since getting locked in the mansion. But today, he ends up triggering one fantastically fun trap after another. Smiling for the first time in ages, Takeshi beams, “I love this stuff!”
Mika head to an abandoned mansion on the outskirts of town after hearing rumors that is houses a terrifying monster. She ends up locked in, but begins searching the grounds. When a strange blue monster appears, she happily says to herself, “Gotcha...”
Except for the monster, life in the mansion is pretty sweet. Using the knowledge gained from the library, the four friends become completely self-sufficient. There’s even a TV in the living room. Eventually, they get quite used to their life and begin thinking they don’t need to escape after all. And in the blink of an eye, 70 years pass...
