Just a typical "progress in a dungeon until you can't progress anymore then leave and stuff happens" game. Basic plot is that the three girls are sisters from a noble family who were saved from monsters by a pair of adventurers; the adventurers sacrificed themselves to save the girls and left their son (MC) behind, who was left at an orphanage. The sisters wanted to adopt the boy into their family to repay the parents for giving their lives to save them, but being from a noble family it would be bad for their image to adopt a commoner boy, so they ended up just helping him as childhood friends.
Fast forward a few years and the boy is attending a commoner's adventurer school while working as a manager and janitor at the all-girls noble adventurer school that the sisters attend (they hooked him up with the job); the two younger sisters are students, while the oldest sister is a teacher. The entire point of the adventurer schools are to instruct people so they can explore a labyrinth that mysteriously opened like 1000 years ago and still hasn't been fully explored.
Anyway, the basic gist is that while exploring the labyrinth with the sisters (all of whom mutually love MC) they find magical devices with powers such as hypnosis and estrus that the other male characters end up using to NTR the three sisters. Gameplay wise the game is pretty boring, though luckily the MC's room has an item that basically gives you free level-ups so the game isn't as huge a chore.
Base +7, KazeSpirit +7, Gnoome +6, nightmare_101 +7, Oushaku +6
were is the room of the MC's and i'm stuck in the part when i meet one of the sisters in one of the boarding school building now i don't know what to do