French text roughly reads: “To kill a guy, nothing better than a good knife! It kills neatly and without noise!” (or without risk — unsure, sentence is full of period slang)
Ekiekipatang
Not a bohemian. He’s an “Apache”.
The “Apaches” were a gang of offenders in eastern Paris, from the beginning of the 20th century.
The gang disappeared in the 20s because, as a large part of french male youth, many of its members were killed during the First World War.