Did 上, ページのトップへ have a tattoo on his bottom lower hip?

i asked this 質問 in Tempo club but since there's wow 1257....well i wanted to get the answer from あなた guys,so i kept watching the コンサート vids,i always keep seeing something black on the lower hip,its not the quality and its not hair,he had his boxers right above his belly button so i just asking if it is a tattoo then cool,if it aint then what is it?