The ones offline on ebay and such are lined. Well mine is anyway..But it doesn't make it any hotter then without it..The one I had commissioned to replace that one is just as hot and it's not lined.
Lining is actually good though too..It helps from being ruined..Like if you sweat the lining gets is and not the pleather. There are other reasonings for lining, but I don't really know them..
Cosplay DA Regular DA
-Fate Testarossa (Mahou Shojo Lyrical Nanoha A's) ~90%-
-Ryouko Ookami (Ookami san and her 7 companions) ~75%
-Amy Sorel (Soul Calibur) 25%-