All perfect praise be to Allaah, The Lord of the worlds. I testify that there is none worthy of worship except Allaah and that Muhammad is His slave and Messenger.
It is not an obligation to get rid of this cup, and it is not forbidden to use it; it is enough to blur the image or scratch it off.
Abu Al-Hayyaaj Al-Asadi said, “‘Ali ibn Abi Taalib said to me, 'Shall I send you for a mission the Prophet once sent me for? Do not leave an idol unless you destroy it, nor leave a raised grave unless you level it down to ground.'” In another narration, he said, “...nor an image unless you obliterate it.” [Muslim]
It should be known that drawing animate beings on utensils is forbidden; An-Nawawi said in Sharh Saheeh Muslim:
“The scholars of our School and other scholars said, 'Making images of animals is absolutely forbidden, and it is a major sin because the doer is severely threatened in the ahaadeeth regardless of whether he did it with a despised substance or otherwise. What he does is absolutely forbidden because it is an imitation of the creation of Allaah regardless of whether it is on a garment, a carpet, a dirham, a dinar, a penny, a vessel, a wall, or anything else. As regards making images of trees or camel saddles and other things in which there are no images of animals, then this is not forbidden; this is the very ruling of making images.'”
Allaah knows best.