PF is paid on the wages paid to the employee. If he has not been paid any wages, no PF is payable. That's all.
Remember that on availing ESI leaves, an employee not only loses his PF share but also loses his bonus for these days. More important point to be noted and conveyed to those who take ESI leaves on unreasonable reasons is that the PF pension which is based on the number of days worked, will also be reduced proportionately if you have more loss of pay days. Only for eligibility for certain benefits like annual leave, gratuity, lay off or retrenchment compensation the days the employee remained on leave without pay (ESI leaves) will be considered as service periods.