Sodomy and masturbation while fasting.
Sodomy is an extremely heinous sin and a cursed act; especially committing this act during fasting is a shameful crime. It will break the fast of both the doer and the recipient, whether ejaculation occurs or not; however, Kaffarah (expiation) is not obligatory. Similarly, masturbation is also a sin, because of which, if ejaculation occurs, the fast will be broken, and only Qada (making up the fast) is obligatory, not Kaffarah. (Kitab al-Nawazil / Vol: 6 / Page: 379)