Sir Doctor of TARDIS. Lucy wondered why there wasn't a name after Doctor. But, well, maybe it was an equivalent term, or... "I think I shall call you Sir Doctor, if you don't mind," Lucy decided. "It seems it has been a lifetime since I met a knight who wasn't a brother of mine too." She considered the ease of 'the doctor', and laughed suddenly. "I knew a wonderful giant named Rumblebuffin. He once mistook me for a handkerchief. It was a bit hard to shout his name in a pinch, though, to avoid him accidentally stepping on you or the likes."