noun
pre-cum; pre-ejaculate; Cowper's fluid
Colloquial term for pre-ejaculatory fluid. Used in casual or sexual contexts.
興奮すると先走り汁が出ることがある。
When aroused, pre-cum may come out.
Also a colloquial term for pre-ejaculate, but 先走り汁 is more direct and less euphemistic.
Compound of 先走り (sakibashiri, 'running ahead') + 汁 (shiru, 'juice, fluid'), literally 'fluid that runs ahead'.