One can get a similar, extremely ugly effect if one is reading Japanese text rendered on a Chinese language system.
Many kanjis in the Japanese text will default to the glyphs in the system Chinese font. However, the kanas as well as some kanjis are not included in the Chinese font will be rendered with a failback font, frequently in a very different style.
Something similar happens when you use Spanish accent letters (á, é, í, ó, ú, ñ) with fonts that don’t include them.
It’s amazing to me that many people seem to not notice or care that random letters don’t match the font style and they keep using those fonts for Spanish.
Many kanjis in the Japanese text will default to the glyphs in the system Chinese font. However, the kanas as well as some kanjis are not included in the Chinese font will be rendered with a failback font, frequently in a very different style.