A local friend from Cologne told me to check out Rosebud bar. After a long journey to Cologne I was tired but went anyway and am I am happy I experienced Rosebud. Being mid-week it was not too busy but had a great vibe. The barmen were very friendly, well-informed and professional.
If you want a cool night out in Cologne I reccomend Rosebud.
Everything from the lighting to the fabrics and marble walls make this bar a definate must when in cologne.