When is it obligatory to slaughter during Umrah? And does scratching the skin, or the falling of eyelashes, or wiping away sweat and tears necessitate slaughter? And is light ablution obligatory to avoid the falling of hair or skin? And does involuntary scratching of the skin necessitate anything?

If a pilgrim in the state of ihram commits a prohibited act other than sexual intercourse or hunting intentionally, they are obligated to offer a fidyah (expiation) with a choice between fasting, feeding the poor, or performing a nusuk (sacrifice, i.e., slaughtering an animal). However, if they commit it forgetfully or out of ignorance, there is no penalty upon them. As for sexual intercourse during Hajj, it invalidates the umrah and necessitates a hady (sacrificial animal) and making up the umrah. The pilgrim in ihram is not required to lighten their wudu (ablution), and it is permissible for them to scratch their skin without any dislike. The Malikis recommended that scratching be done gently for parts of the body that are concealed.