J-HOPE, a member of Grammy-nominated K-pop boy band BTS, began his mandatory military service in South Korea, the second member of the group to do so. The singer kept a low profile as a van carrying him entered the venue for his military enlistment ceremony in the city of Wonju, some 87 kilometres (54 miles) away from Seoul, news agency Yonhap reported. "I'll be back later," the singer whose real name is Jung Ho-seok said on Monday in a post on the fan platform Weverse, alongside a picture of his shaved head. More than 10,000 comments from fans wished him…