In Flemish Brussels dialect, a ket is a kid who grew up in the streets of Brussels. It is widely used to refer to anyone from Brussels. Ketten is the plural of ket :)
Straffe means strong or impressive.
So straffe ket is basically an impressive, tough boy from Brussels.
The name came out of the mind of Tom, one of the founding players of the team, in a crazy brainstorming session where other names such as "Mudballs XV" or "Rugby Club de la Savonette" were being proposed in a festive mood. Once it was thrown into the pool, the brainstorming was over. It was love at first sight, and the team adopted its name and wears it with pride inside and outside the pitch.
As a curiosity, our name even has its own thread in wordreference.
Blue, yellow and white -- the colours of Brussels, the colours of Europe. A slightly deformed pentagon, lifted off the map of our beloved city, a Ket's true home. A rugby ball at the bottom of our hearts. Big bold letters, because we are "straffe" (tough) and unafraid.
Since 2010 the logo has been present on the rugby pitches and also in the rest of our activities.
The logo was designed by two players of the team, Iker and Jens. Jens is a designer in Brussels, if you like the logo you can contact him here.