So "Kimio Namekawa" here is apparently
Yasuhiro Ichihashi, since JASRAC credits composition and lyrics of the in-game version of track 6 to him under his real name and the album version to Namekawa (滑川キミヲ).
Buuuuut, the album credits composition to Mikio Sakai, who is a 100% real person and not Ichihashi, and lyrics to Sora Kisaragi, which may or may not be someone's alias. So I dunno what's up with that.