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
Kumoricon 2014 (so far):
-Sora (Kingdom Hearts 2)
-Alice (Hearts no Kuni no Alice)
-Black&Blue Loli-style Dark Magical Girl O.C.
-Akaito (Vocaloid. Black & Red Ver.)
Dream cosplays for now:
-Tsuruya-san (Haruhi Suzumiya)
-Kagami Hiiragi (Lucky Star)