Rocket porn
I called the conical structure of LS-5 a "payload adapter" because it sits abut the craft, which is a payload. If would be an interstage if it were, you know, between stages. A real interstage structure looks like this:

A fragment from Falcon 1 Payload User Guide.

Also... Weird link of the day: cross-promotion for real-life Japanese rocket girls (actally linked off WOWOW's website) [link]. Debian Women move over, we've got a new fetish here.