The dog was licking him!!!

My fiancé and I are in The process of moving into my house with his dog, he lives in a apartment...traditionally we won’t live together until after the wedding, but untraditionally we’ve started having sex...anyhow...we’ve never had sex at his place in the last year, and decided to christen it for fun. Mattress on the floor and all we start to do the deed, usually we put the dogs away if we’re going to have sex so they don’t bother us. We decided not to this time because she was in the other room. If we’re doing a quicky that can be anywhere from 5-10 min. We werent planing on staying their, so we just wanted to get it over with, not In that way, just say we did before he gets rid of it. He was taking more then ten min, I don’t know why, all of a sudden his dog comes and starts licking him while he’s ontop of me, I kept shooing her away, and finally he’s like just let her screw it. Um..................ok?🤔😳 she starts licking his ass and he immediately came! Ummmm....😑 wtf? What the hell do I make of this??? I’m so grossed out... I’m like confused frustrated and disgusted all at once and don’t want to have sex when he gets home, and it’s my fertile window. Am I being dramatic????? Is he letting his dog do shit to him? Am I loosing my mind!? You