Is it normal that my dog licks my pussy

Here let me help you out since you think you're so smart.

Having a large amount of sex is not in and of itself a disorder. Enjoying sexual activities even deviant ones is not in and of itself a disorder.

These two things are situational characteristics that could potentially be applicable to a mental health diagnosis.

Let me further explain -

Human sexual relations release many neurological chemicals, these chemicals create many wonderful feelings in humans. Seeking these out is a perfectly natural thing for humans to do, yes, even in what you perceive to be excessive amounts. The difference between an amount and the impact of an action is that doing it 4-7 times a day is irrelevant if it's not negatively impacting them.

So from that we draw a possible scenario and response -
If the individual is doing the sexual act instead of an appropriate action that could otherwise benefit them and therefor the sexual act is causing a negative impact on their life, then we could say that their pleasurable activities are in fact detrimental.

HOWEVER - If the act is not interfering with life events and is done in a proper place and time then it is not considered an addiction or disorder. The only caveat to this may be the possibility of a chemical imbalance due to prolonged over stimulation which can take months and is usually relatively simple to explain and suggest hey, don't do it 4-7 times a day - do it once a day or it might become a problem LATER, but the occasional...like once or twice a month of 4-7 times in one day is fine.

Now on to your next belief of ethics and psychology being involved.

There is no evidence to suggest that having a sexual relationship with an animal is directly detrimental or indicative of a psychological impairment, ethical or moral compromise. What that means is that just because a person lets a dog lick them doesn't mean they are somehow violating any of the things you think they might be. It's still an irrelevant sexual act without some sort of contextual parameters. Such as being "in Love" with your dog, that would be grounds for concern, however just understanding that your dog can provide you with pleasure is not in and of itself a mental disorder.

Next on we have the medical side of it - This specific interaction between a human and dog has no signs of any medically dangerous actions. Now if a dog mounts a person and engages in intercourse with them they can be quite large in some areas and that may cause issues. The only other thing to note is that if your dog is unhealthy, much like human partners being unhealthy it can be unhealthy for you. So as long as the dog is healthy there is basically no reason for concern aside from some scratch marks.

Did I miss anything?