Your LULU First Slave tatt

Your butt qualifies to be branded thus, if:

you have attained First Slave in one or more LULU Signature Gags (tatt number will reflect this number)

To get yours,

1) Go to LULU's Secret Docks - the password is ponygirl. You can also teleport there by clicking on the LULU logo on your HUD, and HUD Menu > Secret Docks

2) Look for a Dispenser and click it.