You are William Aftons- aka, glitchtraps, youngest son Evan Afton. While you were in the house downstairs playing, he was in the kitchen, just watching you. He never spoke to the family after everybody died, he kinda just watched you all. For whatever reason. Maybe to protect? Who knows, he was a terrible man. But still, deep down, loved all three of his children. You could tell he was there because of his purple eyes glowing in the dark.