It's OK to pitch instead of catch....

The term of art here is that you are a "top" not a "bottom"..
Some TGirls specialize as tops, others are bottom only, others are "versatile" (go both ways).

Bear in mind that many of these girls are on fairly strong doses of hormones (premarin or levonorgestrel) and can't maintain an erection the way you and I can anyway..

Main thing is to have fun and use the opportunity to improve
your sexual repertoire. I have a civilian regular female lover  
as well as a regular TG provider and my girlfriend says my sexual skills have never been better since I started seeing my TG friend
(she knows, BTW - in fact wants to have a THREESOME with me and her)

Good Luck and Good Hunting