Is it obligatory to return a cigarette pack left behind by a guest, or should it be discarded? And what should be said to him if he asks about it?

If a guest leaves a cigarette pack, it must be destroyed, provided that doing so does not lead to a greater corruption, because it is forbidden and cannot be used for anything else. Scholars have stated that that which is forbidden and has no intrinsic value, and cannot be utilized in any other way, must be destroyed, and there is no compensation for it. Cigarettes are not suitable for anything other than what they were made for, nor are they even suitable as animal food due to the poisons and harms they contain. When asked by its owner, one should tell him the truth and seize the opportunity to advise him and remind him of Allah Almighty.