This is a FCS-only head mold. It was released at Tenshi no Sato in September 2015, then to all Sumika locations in September 2015. The Full Choice Handbook: 2016 by Volks shows the head mold with 18mm eyes.

This description is from Volks promoting the sculpt on Facebook for their NA Online FCS:
"Today we would like to highlight on a new release SD head mold, the SD-F-58. Their sharp features give you a sense of maturity and coolness. As a girl, we get a feeling of a cool older sister who is perfect at grades, sports, and art and we aspire to be just like her! As a boy, we get a feel of a cool older brother who can solve any problem yet still teases you when he feels like it!"

Please click on the individual thumbnails to see the pictures full-sized.