I was thinking of two songs I've met through anime that are really special to me, namely, "...To You" by Ayako Kawasumi, the opening from the small anime "Piano: The Melody of a Young Girl's Heart"; and "Never Looking Back" by Shizukunome, the second ending to You-Gi-Oh!! SEVENS.
So, what are some small pieces you'd like to highlight?
ZAQ's Soranone comes to mind. It was used as opening for Kouya no Kotobuki Hikoutai from 2020, which is not well known and underrated itself. I think ZAQ is underrated in general among western community, so basically any of her anisongs could fit.
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