My ex is a ***

okay not exactly a new story but i found out my bf was cheatin on me the other day with one of his exes so i dump him. Thats the very shortened version, i left out the details of violence, lies and generally suckiness.
So i find out today hes going round saying i fucked him on our 1st date. fucking asshole. Im pissed off rite now so even thou nobody here knows him feel free to slag him off