you like it because it gets you aroused by the fact you love the feel of a man's penis getting hard in your mouth and knowing how much you are satisfying him by swallowing his cum and tasting his semen. might also love it because its makes you feel like your good at it when you make him cum. some girls find giving oral is nasty but if you like hey run with it. it also probably makes you feel like you have control over him,like putty in ur hands when u give him oral.
Placing our mouth on a lover's genitals is one of the many wonderful sexual situations /sensations we can experience as humans. It satisfies a special need for many -- an ultimate, intimate craving -- and is only one part of our sexual "repertoire". To my mind, a fully rounded sexual being can find pleasure in aspects of sex with either gender, including playing with / swallowing either sex's ejaculate.