[CHz]

The music here all seems to have been produced by Sound AMS, so momo should be Momo Michishita, koutaro should be Kotaro Tamura, and hiro-pon, well, there's Hiroki Matsunaga, Hiroshi Watanabe, and Yasuhiro Tamaki. I'd guess it's not Matsunaga, since he's already credited on a few songs under his real name, but you never know.