The month of May is a storyline-generation machine for European soccer. There are titles getting decided everywhere, anxious relegation races to follow and tickets to UEFA competitions to punch. There are also, of course, the final rounds of said UEFA competitions. If something memorable is going to happen in a given season, the odds are good that it will happen in May (or, when there are strange circumstances like, for instance, a winter World Cup, early June).
Even taking title races and the Champions League out of the equation, there's just so much to follow.