I recently got in a relationship my gf and her family is so open that for me it's weird and incomprehensible. My gf called me stay in her house with her when I came there I thought she was having separate room but she was sharing it with her younger sister. I talked to her and she said it's alright with her there we can enjoy ourselves. We had a sex at night it was weird for me as the younger sister was there with us. In morning my future mother in law was ok with it she even said in joking manner that if one is not enough go for other sister. I don't think it's joking subject it make me weird and uncomfortable. As the room is shared when I enter most of time sister in law in her underware and most of the family is ok with it am I so old.