The rock den's celebrating V-Day two ways: Friday's fairly hardcore, with $3 imports, $4 Kilo Kai/Absolut cocktails, tawdry burlesque, "virtual freak show" Reverend B. Dangerous (he drives nails into his flesh!), and metal band Skank. Saturday keeps the $4 drinks, with mellower entertainment provided by four indie bands headlined by The Chamber Strings, whose jauntily melancholic style survived the singer's lengthy heroin addiction (what you got, Skank?).