Prince is a 20-year-old from Minneapolis who writes his own songs and plays all musical instruments on his albums (but performs with a band in live shows, as at the Ritz last Tuesday). ... He likes to throw a little shock treatment at the public by wearing bikini underwear as part of his stage costume (‘I’m comfortable that way’) and by doing songs like those on his latest album, ‘Dirty Mind’ and ‘Do It All Night,’ for instance. ... Prince says, ‘A lot of politicians are basi

“Prince is 20 years old and has a self-proclaimed ‘dirty mind.’ His newest album on Warner Brothers Records, which he produced, arranged, composed and performed himself, includes a sensual song called ‘Sister’ which takes an unorthodox view of brotherly love. Another graphically erotic ditty, ‘Do It All Night,’ is . . . er . . . self-explanatory. He’s pictured on the front cover in just a black g-string and short jacket, and he’ll wear the same garb when he appears in his ‘Al