I could write a book on this subject because I have a weird cum fetish.
I don't watch porn, it doesn't do much for me, but show me a video of a guy that masturbates and shoots a boat load of cum and I get instantly horny.
In real like I don't want to be covered in cum and cum on my face or in my hair is a turn off, but what turns me on is a huge cum shot in my mouth or inside of me. It turns me on to feel my mouth getting blasted and filling up with cum (I may not swallow it) but just feeling it shooting in there is erotic.
Inside of me is erotic when it drips out, I like seeing and feeling a lot coming out of me. I also seem to drip cum for some time after sex, and that is an erotic reminder. The bigger the load, the longer and more I will drip, sometimes as long as 24 hours later.
One of the most erotic things I have ever seen in person was when a guy pulled out of girl and shot his load, it went and hit the wall behind the bed, covered the headboard, her face, breasts, stomach and vagina. He shot for about 15 seconds solid long hard streams and she was covered. I nearly had an orgasm from just watching that in person, I would not have wanted to be her but it was amazing.