THEORY: This was a handle of
Takashige Inagaki.
TOTALLY CIRCUMSTANTIAL EVIDENCE:
- Takashige Inagaki was part of Same Creative. Gakkie is (was?) part of Lip on Hip.
- Lip on Hip is a subsidiary or brand or something of Same Creative, and there is staff overlap. Mitsuhiro Tabata of Same Creative = WACHA of Lip on Hip, Koichi Ishibashi = bAsHEE, etc.
- Gakkie's last known works happened around the same time that Inagaki died (R.I.P.).
- Name similarity: Inagaki -> Gakkie
WHY I AM PROBABLY FULL OF IT:
- Inagaki seems to refer to Gakkie as a different person in this interview: http://ar-tonelico.jp/dokkoi/index_01_20.htm (question 3, first answer).
- Likewise, Gakkie is credited along with Inagaki on a bunch of Ar Tonelico albums, although never for the same role I don't believe.
Feel free to spike other gigantic holes in my theory here!