Moonlit Mansion: The Lion (月光の洋館：ライオン)

You wake up locked in a prison cell inside a vast, fog-filled mansion lit by cold moonlight. Something with a lion's mane roams the halls. Each day, finish a mission, then return to the bed in your cell. If it sees you, it chases until you break its line of sight; inside a locker it can never find you. Survive ten days and escape through the front door. Progress saves automatically, collected items stay even if you are caught, and once the mission is done Senpai leads you back. Beast Senpai escapes with you, sometimes calling out where the lion is or drawing it away as a decoy, but if it catches him he is sent back to the first cell. Normal and Hard modes.