In the garden the devil haunts. Undoubtedly. After all, he has a goat beard and horns. Or is this just a fool's cap carrying the strangely bagged bronze giant behind the K21? His coarsely shaped face seems rather strained, as if he snatched for air, the fine hands seem to conduct, one up, one down. Could also be a politician. Or anyone's plagued soul. The riddle belongs to the background work of Düsseldorf sculptor Thomas Schütte, who arranged a…