pet and I are currently discussing how to best apply Crisco into ass. Best we have come up with is an icing bag squeezy thing.
I am not sure that the cake decorating bag would be stable enough, I do like the anal speculum but if you are looking to squirt it in I also thought about a giant syringe like is used for tube feeding. Put the crisco in the open end and then simply push it in. Oh and you might want to cut part of the end off so you don't have to push so hard. You might heat the crisco up just a tad to help it move.
here is a link to a picture of what i am talking about.
http://hambydairysupply.com/xcart/product.php?cat=108&js=n&page=2&productid=1491
Sorry for the long link I hope it works.

