بسم الله الرحمن الرحيم
Q: If sexual relations are numerous during the day, or throughout the month of Ramadan, is the expiation numerous as well (according to the amount of sexual encounters)?
A: What is known from the jurisprudence of Imam Ahmad is that if it is numerous in a day and no expiation is done for the first sexual encounter, then one act of expiation suffices (for the sexual encounters throughout that day). But if there are several sexual encounters within two days, obligated upon him is an expiation for each day, that’s because every day is an independent worship.
Translated by Najeeb Al Anjelesi
Source: فتاوى في أحكام الصيام