Porn
Alina Yeremenko, a porn actress who uses the stage name Alina Henessy, offered Kokorin the proposition when he played for Dynamo Moscow in 2015.
While chatting to Russia Eurosport, Yeremenko was asked to rate Russian players out of 10 based on their looks.
Kokorin was given 10/10 and after hearing he was struggling on the pitch, she sent him a personal message.
"If before the end of the championship [Russian Super League] Alexander Kokorin scores five goals, I promise to hold a 16-hour sex marathon with him as a thank you," she said to a shocked studio.
The claims were made in April and Moscow had 10 games of their season left.
Kokorin only netted one more time that season and finished with a respectable 10 in 39 appearances in all competitions.
He'd end up spending another season in Moscow before securing a move to Zenit, with who he won the Russian Cup and Russian Super League respectively.
The forward now plays for Serie A outfit Fiorentina but is yet to score since arriving in January.
If for some reason you're wondering what other players Yeremenko rated, then there are a few you'll remember.
She gave former Arsenal winger Andrey Arshavin an eight for being 'cute' but then came down hard on Yuri Zhirkov, who was given just a four.
Kokorin often finds himself wrapped up in weird and wonderful stories like this.
He played alongside World Cup winner Adil Rami at Sochi for a season and caught wind of his romance with actress Pamela Anderson.
"Rami told us a lot of interesting things about Pamela Anderson," Kokorin told Alexander Aliyev.
"Of course, everybody was interested in what their relationship was like in bed. Rami said that Pamela was the best woman he'd had in his life.
"He said that he and Pamela used to have sex 12 times a night."
It could've gone much worse. Just ask former Croatia defender Dino Drpic.
He was once transfer listed by Dinamo Zagreb after his then-wife, Playboy model Nives Celsiu, admitted the couple had sex in Stadion Maksimir centre circle.
