This troper shared a University residence with 10 other students, one of which was named Peter. I went almost all of the first semester (after which he moved out) without seeing him. His door was always closed, he never ate dinner with anyone else, I never even saw him in the kitchen, he never came out to watch TV, never appeared at Unit meetings etc. After a while I was starting to imagine either a
Captain Tuttle situation, or alternatively that I had seen him and just assumed he was visiting from another unit. Neither was the case - I met him about a week before the midyear break and he was not someone I'd met before.