Love Irisu Syndrome, wish it got more popular

いりす症候群!滅 BGM集

思惑は4つ透りぬけて (Four Translucent Speculations) - Irisu Syndrome!

Plays during a secret cutscene after you get to level 100 in Metsu mode.

Usagi Note, from Irisu Syndrome. Composer: Takeaki Watanabe