Polyester? It's not 100% poly I can tell you that..100% poly has zero stretch, meaning it would stay one size and never hold itself up without elastic, which will look bad..Most things that have stretch that are poly are a cotton/poly blend, but I wasn't sure if that has an actual name..so..
Cosplay DA Regular DA
-Stocking Anarchy (Panty & Stocking. Normal Ver.)
-Sora (Kingdom Hearts II Final Mix+. Limit Drive Ver.)
-Kyoko Sakura (Mahou Shoujo Madoka Magika)
-Akaito (Vocaloid. Black & Red Ver.)
-Marluxia (Kingdom Hearts Chain Of Memories)