Isaku
A 1995 mix of Visual Novel and Adventure Game, Isaku is a story about ten people inside a closed building.
Kenta Kogure is your average Japanese high school student. He has a crush on his classmate Kotomi Asakawa, is crushed on by classmate Rika Akagawa(a crush he is completely oblivious to), and have a great friendship with fellow student Jinpachi Shimada.
He receives a letter from Kotomi one day to meet him late at evening at an abandoned school building. Obliviously, he walks in, and soon discovers Rika, his homeroom teacher Takashima, Jinpachi and five other of his female classmates received letters that led them to the same room on the fifth floor of the building. The one exception: Munemitsu Soga, a rich boy that stalked Kotomi to the same room.
They soon discover they're locked inside the building, and that Isaku is keeping them locked in for unclear reasons. With internal secrets creating conflicts between students, Munemitsu barely hiding how much he wants Kenta to disappear, and Isaku somehow being able to move without being seen, escaping from the old school building will be an herculean task.
The game revolves around finding exits for the floors of the building, examining rooms and discovering anything that can lead to find the keys. There is also dialogue options that may lead to characters being captured or escaping Isaku's clutches.
Developed and published by elf. It was adapted into two anime OVA series of same name in 1997 and 1999.
Not to be confused with Isekai.
- Accidental Murder: How Jinpachi describes the death of Miyuki's little sister. Miyuki, however, is aware the moment his story ends that was not how she died, since her cause of death was concluded to be asphyxia.
- Adults Are Useless: Takashima suffers a mental breakdown around the time Jinpachi disappears, and Miyuki and Kenta do more of the heavy work. This is eventually deconstructed at most endings, where she leaves teaching out of guilt.
- Anti-Hero: Kenta is able to do many perverted things to the girl, like looking at their panties when given the opportunity.
- Big Bad: Isaku, the janitor who imprisons the cast inside of an abandoned school building.
- Bittersweet Ending: If you don't save everyone of Isaku, the ending is this, with Kenta graduating along his saved friends but missing Jinpachi and the not saved leaving the school forever.
- Blood Knight:
- Mio was brought up to the building by an anonymous letter challenging her to a fight.
- Isaku deliberately leaves Kenta alive after stumbling onto him because he feels the other students will never solve his challenges.
- Defrosting the Ice Queen: Kenta slowly manages to convince Miyuki to like him since he becomes so useful.
- Eerie Pale-Skinned Brunette: Miyuki has dark hair, milky white skin and seems to look down on everyone, even after Kenta becomes pretty useful and the group rallies around him.
- Golden Ending: Saving everyone leads to Kenta becoming either Kotomi or Miyuki's boyfriend.
- Green-Eyed Monster: Munemitsu becomes very quickly violent towards Kenta for finding the keys and earning admiration of everyone. By the third floor this turns physically abusive. He mellows down after being tied down by Isaku; whether if you find him or not before he is raped.
- Heroes Want Redheads: Kenta has a crush for Kotomi and she haves bright red hair.
- Hot Teacher: Kumi Takashima is pretty curvy and pretty.
- Kill'Em All: Going straight to the first floor without progressing Jinpachi's subplot after Akemi freaks out leads to Akemi setting the building on fire and killing everyone.
- Meganekko: Rika has large glasses and is reserved.
- Panty Shot: Kenta has several opportunities of staring at the girl's panties.
- The Mole: Miyuki becomes increasingly suspicious that Jinpachi is one for Isaku as of the second floor. She is absolutely right.
- Sanity Slippage: Akemi, Munemitsu and Takashima's mental states degrade with the confinement.
- Spoiled Brat: Munemitsu's family is described as very wealthy, and Kotomi says he turned from the sweet boy she knew into the jerk he is now because of his father.
- Stalker with a Crush: Munemitsu seems to follow Kotomi everywhere and is disturbingly envious Kenta may win her love.
- Teacher-Student Romance: Akemi's boyfriend isn't a college student, but unseen high school teacher Yoshizawa.
- Token Loli: Though she is the same age as every other student, Rika is petite and Kenta even describes her as looking like a elementary schoolgirl.
- Tomboy: Mio is very manly in behaviour and got involved in the plot at the prospect of a fight.
- Used to Be a Sweet Kid: How Kotomi describes Munemitsu, and says his father changed him.