Santa gifted this to my 16 yr. old for her Birthday... She loves it & so do her freinds at school!  It's thick / sturdy cotton, fits well - She's a size 4-6 (Women's), 5'6" Tall, 125 lbd, the Medium fits well, without being either too tight, nor overly baggy.  Just right.  I think the sz Small would be for a more petite girl (ie sz 0-2). Best gift ever for BtVS Fans! Cheers!