Sei Leise is a Cologne street artist who started graffiti as a teenager.As a trained graphic designer, he fell in love with urban art early on and has been a street artist since 2012.He became known through reverse graffiti, which is only practiced by a few artists.Murals are created by removing or leaving dirt.However, he now works mainly as a paste-up artist and his work can be found on the streets of Lisbon, Hamburg, Paris and London.Above all, however, in Cologne, his hometown.Wind, weather and passers-by ensure that his paste ups are ephemeral, a special attraction of this art form.