Chav rash is essentially what are normally called lovebites. It would seem that there is a growing trend among the younger generation of chavs to spread chav rash as if in some way marking their women for all to see.
"I was disturbed to see that not only was the 12-year old chav pregnant, but she also had a nasty case of chav rash all over her neck."
Chav Rash: after getting a rash from a dodgy kebab, some crazy rash enveloped him. causing him to lie on whitey's kitchen floor in pain, getting ripped by whitey and emery. 'haha, you've got a rash!! haha, you've got chav rash!!! hahaha!! no way, you are Chav Rash!!!! this G graffs and MCs under the name Chav Rash or C.Rash
yo Chav Rash! what you up to homes??
oi rash!! save me twos?