Figure

To evade Figure, you have to crouch around him. You shouldn't hide in closets or you have to do a heart minigame.  His hearing is super good, and do NOT walk standing up.

Figure appears 2 times in game, one in the library scene, and one in the final boss. He has no eyes, but SUPER great hearing.

Figure is not rare, but predictable. He always appears on doors 50 and 100 for the boss fights. If you want rarity, it depends on how far you get in the game.