The film GF-09 is also featured in studio JAMS' Ultimate Collection series 10 (JCD-10).
GF-09 is a film produced by studio Agastia, and is the 9th instalment of the studio's Giant Woman Workshop series (that's the name I could find). The production stars a model by the name of Naomi.
Studio Agastia later turned into the studio which is now known as JAMS. Studio JAMS eventually created the "Ultimate Collection" series, commonly referred to as (JCD).
Many of the old studio Agastia productions can be found in the JCD series. Unfortunately, the JCD films appear to be almost as rare as the GF films.
Here are some sources on this production:
Agastia GF-09 Archive - https://web.archive.org/web/20050305120834/http://www.agastia.com/GF/GF09.htm
JAMS JCD-10 - https://www.arzon.jp/item_678821.html
On a different matter... RE-09 is a production I am eagerly searching for. It's also featured in studio JAMS' Ultimate Collection series 4 (JCD-04). It stars a model known as Kana, Kana Hanashiro, Mistress Kana, Queen Kana, Queen Kana Hanashiro or Glamorous Queen (misspelt as "Glamourous Queen").
Some sources:
Agastia RE-09 Archive - https://web.archive.org/web/20050321033238/http://www.agastia.com/RE/RE09.htm
JAMS JCD-04 - https://www.arzon.jp/item_678825.html
She also features in the following JCDs:
JCD 13 - https://www.arzon.jp/item_480519.html
JCD 15 - https://www.arzon.jp/item_480520.html
JCD 24 - https://www.arzon.jp/item_480529.html
I know there's a 15 minute clip floating around out there, but I'm searching for the full thing, either RE-09 or JCD-04. If you have any info on it, or if you wish to help me search for it, please DM me. It's a great production! Thank you and enjoy.