I love to jack off imagining to have sex with an other guy's gf or wife.
It's more exciting to me.
Frankly speaking, I'd love to fuck my older brother's gf.
Specially a fantasy of playing with her gives me stronger orgasm than real sex with my gf. Because she is a girl of brother's, not my cup of tea, I'm crazy for sleeping with her. I know it's a very immoral and dangerous idea. I don't wanna make myself a problem-maker, either but I cannot stop thinking it.
I must be a bad younger brother.