The defining feature of an "ultra lounge" is "bottle service." It's a Las Vegas conspicuous consumption thing that has spread beyond Vegas.
You walk in and spend $250 for a whole bottle of Courvosier (or other trendy spirit) that you could buy at BevMo for $40 or less.
In exchange for that you and up to 9 friends (most bottle service bennies top out at 10 people, but some ultra lounges set the max lower) get to sit at a table in a space reserved for folks buying bottle service. These tables are often in restricted-access areas of the bar, but are highly visible from just about everywhere. In a nod to tradition, bottle service areas are usually cordoned off with velvet ropes, with an officious maitré'd /bouncer making sure the riff-raff doesn't get in.
You don't get to touch the bottle. You get a dedicated server who pours your drinks. There's often quite a bit of tipping expected during this process.
At the end of the night (or the end of the bottle) you've got a few hours being seen by the masses spending ridiculous amounts of money.