Soejima was born in Kanagawa Prefecture, though his family moved quite often during his childhood due to his father's office work: a month after his birth, his family moved to Machida, Tokyo, and in future moves relocated Fukuoka Prefecture, then back to Machida and then to Suginami.
For Persona 3, Kaneko put Soejima in charge of art direction for the Persona series, as Kaneko wanted Soejima to grow as a designer [REF].