Done wrong, this can be painful and yes, dangerous.
First of all, throw away the Anal Eaze. I personally hate this stuff and think it is unsafe! Anal Eaze has a numbing agent that causes both the penis and rectum to get numb. Pain is God's way of telling us that something we are doing is bad for us, and STOP! Also, if the penis is numb, it takes more stimulation to get off, meaning more friction, longer time to orgasm, and more pain for the receiver. Admittedly, S/M'ers do get off to a certain degree of well-placed, well-thought-out and consensual pain, but personally, I don't think this is an area that should hurt. If it hurts, you are doing it wrong.

OK, you've thrown away the Anal Eaze and your partner has agreed to try it. Now what? Foreplay, foreplay, and when you think you've had enough, more foreplay! Don't rush this, as that is setting the receiver up for a bad experience. You must prepare the area. Use plenty of lube (I find that a silicon based lube is best, as it does not dry out or soak in). Now, slowly and gently insert a finger or small butt plug. If it is a finger, BE SURE THAT YOU DO NOT INSERT THIS FINGER INTO THE VAGINA. This can cause very serious infections. Be patient, as this is a slow process. Check with your partner to make sure there is no discomfort, and then leave it fairly still for a little while for the receiver to get used to the object. Move the finger of plug around slightly but very slowly and very gently. Don't insert, take out, insert take out, insert take out. You get the picture. Again, this is not a pussy! Slight fucking motions maybe, if your partner is OK, but inserting and taking out can cause discomfort. Next, add more lube and move to a larger plug or try adding another finger. When you get to the point where three fingers or a larger plug is comfortable for your partner, it may be close to time to try the penis. Get into the desired position. I've heard from a lot of women that they prefer to lay on the stomach. Add more lube, then add some more. There can never be too much lube!! Very slowly and very patiently, insert. DON'T RUSH THIS! Go a tiny bit at a time, then give the receiver time to adjust by holding still. Go a bit further, very gently and patiently until the whole length is inserted. Here's the biggest mistake that most men make in this act: Pulling almost all of the way out and re-inserting, as you would during normal intercourse. This motion is the largest cause of pain, aside from rushing. The penis should not move more than about ½" to one inch during the act of anal intercourse, if you want it to be pleasurable. The sphincter muscles automatically try to go back to the natural, tightened position every time that the object holding them open is removed, so the standard fucking motion causes them to expand, contract, and try to push the object out. Pushing (as opposed to pushing and pulling) and staying in pretty much the same area is much less uncomfortable for the receiver than fucking like you would in normal intercourse. Rock back and forth and push as opposed to extreme in and out penetration.

It is extremely important to keep in mind that bacteria from the rectum can cause horrendous infections if this bacteria should make its way into the vagina or urethra. Make absolute sure that your toys are clean, and to be safe, do not use toys that have been used anally in the vagina. To be safer, you can cover the toys with condoms, but the best bet is to have toys designated as 'front' and 'rear'. If using the fingers, latex gloves are a very good investment!

My recommendations in this area: