“Lavish” just might be the perfect word to describe the Back Bay’s chic Stix Lounge (35 Stanhope Street, Boston, 617.456.STIX), with its illuminated liquor bottles perched behind the bar and the alluring glow of strategically placed lighting. So it seems fitting that every Thursday night at 10 p.m., 235ent.com and V-fit are hosting their new Lavish Thursdays there. All they ask is that you dress in a trendy and stylish manner (duh — check) and enjoy listening to Top 40, mash-ups, and house music. And did we mention that there’s no cover charge?