Rika Furude from Higurashi? c:
How about one of these? I've seen people do dark blues, and purples, so i'll suggest both.
Purple:
http://www.ebay.com/itm/Flat-bangs-and-long-straight-hair-violet-high-temperature-wire-cosplay-wig-/280859249902?pt=US_CSA_MWA_Wigs_Extensions&hash=item4164840cee#ht_2911wt_1037
or
http://www.ebay.com/itm/Belem-Castelnuovo-100cm-exposed-dark-purple-high-temperature-wire-cos-wig-/280860109419?pt=US_CSA_MWA_Wigs_Extensions&hash=item4164912a6b#ht_2833wt_1037
Blue:
http://www.ebay.com/itm/D1397-Deep-blue-luck-the-tail-of-the-fairies-cos-wig-100cm-/290698243620?pt=US_CSA_MWA_Wigs_Extensions&hash=item43aef72e24#ht_2842wt_1270
or
http://www.ebay.com/itm/2085-NEW-Fashion-wig-animation-blue-neat-bangs-Straight-cos-Wig-100cm-/300669626381?pt=US_CSA_MWA_Wigs_Extensions&hash=item46014e680d#ht_1587wt_1270










