Initially haikai no renga distinguished itself through vulgarity and coarseness of wit, before growing into a legitimate artistic tradition, and eventually giving birth to the haiku form of Japanese poetry.
Haikai no renga, in response to the stale set forms that preceded it, embraced this vulgar attitude and was typified by contempt for traditional poetic and cultural ideas, and by the rough, uncultured language that it used.
A well-known example of this early attitude is the opening couplet, possibly by Yamazaki Sōkan (1464–1552), from his Inutsukubashū (犬筑波集, "Mongrel Renga Collection").
He was given the following prompt: 霞の衣裾は塗れけり kasumi no koromo suso wa nurekeri The robe of haze is wet at its hem to which he responded: 佐保姫の春立ちながら尿をして sahohime no haru tachi nagara shito o shite Princess Saho of spring pissed while standing[3] This poem clearly derives its humor from shock value.
[4] Taking an ostensibly traditional and poetic prompt and injecting vulgar humor while maintaining the connection of the damp hems and the spring mists was exactly the sort of thing that early haikai poets were known for.