The defender - himself no stranger to controversy - has suggested the Barcelona man lacks human decency.
Pictures emerged following the Clasico in March that showed the Portuguese defender suffering a blow to the head while on the floor, courtesy of the Blaugrana midfielder's boot.
Busquets denied he had touched the Blancos centrer back despite the photographic evidence, with Pepe saying his rival lacked decency.
"No one is that silly, there are pictures proving it happened," the 31-year-old told reporters following the club's 3-0 win over Borussia Dortmund in their Champions League quarterfinal on Wednesday. "One of the values of a human being is to be honest and admit at times knowing when to apologize.
"If instead of Busquets it was me, then I would not be playing for Real Madrid, which is what many want, to see me outside the team. If it was me who did it, people wouldn't want me in Spain. I seem to have the reputation of a murderer, they'd cast me out.
"But these things happen in football, of course I'm happy at Madrid."