Really?....you had to look this up? Very well...pay attention.
A Dirty Long Jon is what you get after assfucking a bitch while smoking a blunt of that good bubba kush so you forget to clean her out and when ya nut and pull out ya got a mix of cum and shit all-over your long Jon.
"That nigga was high as fuck with Kesha last night and pulled a Dirty long Jon"