I one time heard my dad and his girlfriend having love in her apartment. Me and her son(who introduced me to Blockland) were chilling in the living room and we just looked at each other like "omg they're doing it." I was 12 years old.
I later talked to her about it, and she remarked that he "still has young meat," despite the fact that he was 51 at the time.
Try living with your loving grandparents (61 and 75) and being in the room next to them, while in a skype call with someone, on their anniversary