BACKTAGGING: always
FOURTHWALLING: sure, why not
PHYSICAL AFFECTION: I am very much all for it, but the Doctor will be deeply resistant unless it's from someone he has very close CR with
PHYSICAL VIOLENCE: Yes, but please discuss with me first!
RELATIONSHIPS: Yeah! The Doctor is extremely long-lived and falls in love many times over though, so if someone wants to be in a relationship with him it should be known that he is married and in love with others (River and Clara) already >.>