This is a reasonably well-known photo of Kafka, looking - well - somewhat un-Kafka-ish. Not that it would make him look any more the sober observer, but this photo is cropped from the original. The full photo has a lady holding a parasol to the left of the dog. The lady is reputedly a lady of broad morals, and it was she who insisted the photo be taken.
Kafka was not his usual self because of his escapades earlier in the evening. His friend Max Brod, with others, had encouraged Franz to a night on the town. Their idea consisted of pubs and carousing. Kafka - as they well knew - did not drink more than the occasional ale. And, he much preferred the coffee houses, where more literate and intellectual conversations were to be found. So, after some token protests, Brod and the others agreed to a coffee house. They chose a specific one which had the reputation of at least having some avant-garde patrons. Kafka relented to this choice.
Unknown to Kafka, the fix was in. Brod had arranged for the coffee brought to their table to be laced with brandy, with a touch more milk and sugar. And Kafka did make mention that it was a bit sweet, but the others did not complain, so he said no more.
As Brod recounted later, Franz had his usual three cups, and then one more. His talk was animated, and he participated more than usual in the conversations. When the young lady with the dog was introduced, he was effusive, as he had a great liking for the companionship of women. Having the photo taken was the woman's idea and, as perhaps can be seen by Kafka's expression, the brandy was finally having a more subdued effect.
And yes, gentle reader, all this took place on April 1st.