I could understand that if a girl doesn't get over the initial shock of having a penis in the butt.
First time I tried it with my g/f I felt bad for her.. and a little grossed out.
Second time I tried it with another g/f, no problem.. but still grossed out.
Will I do it again? YUP.
BTW, facials aren't fun because that's what they want.. I rather put it somewhere more entertaining, like her hair.