Is it normal that i spend so much time with my face in her butt crack

My girl friend got me into this when she asked me to give her an enema before we showered together. It was morning and she invited me into the bathroom while she pooped. We actually both pooped. She then brought out this contraption that I found out was an enema bag. She filled it with a special soap and we both took turns inserting the tube in each other's butts. We did it a second time with a special flavored liquid added to the water. We took a shower and scrubbed each other's butt cracks real good. I got down on my knees, she bent over and spread her cheeks while I licked her butt hole and licked her more from front to back. We went to bed where she brougth out a special cushion. She bent over it so that her sweet behing stuck up in the air. I ate out her butt crack while she moaned with pleasure. She then rolled over and I tongued her little clit button until she came like a animal. She did my butt and dick also. We ended our little session with some doggy style fucking. It was so much fun. We do enemas all the time now and spend a lot of time in each other's butts. Spankings are also traded when we feel especially naughty.