中国篮球巨星蔡徐坤

Based on your description, you might be referring to Cai Xukun (蔡徐坤). He is a popular Chinese singer, songwriter, and entertainer who has amassed a large fanbase. Cai Xukun became a viral meme associated with basketball due to a promotional video where he was seen playing basketball, which led to the ironic nickname "basketball superstar" online. He is also known for his distinctive fashion style, which sometimes includes wearing overalls.