泥鰌汁に金鍔
Meanings
1
two things that don't go together; mismatched pair
Idiomatic expression likening a mismatched combination to serving loach soup with kintsuba (a sweet bean jelly). Used for incongruous pairings, often humorously.
See also: 金鍔 (きんつば)
His suit with sandals is exactly like pairing loach soup with kintsuba — two things that don't go together.