Bloodborne has the word blood in the title. It's also a violent video game in which blood will most likely be shed. Therefore this makes complete sense: in Denmark if you give blood, they will give you a copy of Bloodborne for the PS4. Seems like a fair trade!
It's part of a promotion between Sony Denmark and GivBlod, a Danish organisation similar to Donate Blood here in Australia. Apparently convincing males to donate blood is difficult and there is a shortage. GivBlod decided — sensibly — that video games were the answer. Bloodborne in particular was the answer. Anyone who donates blood at an event in a specific spot in Copenhagen between 12 and 5pm on March 23 will receive a copy of the game.
It's interesting to see GivBlod going down this route. Last year Donate Blood also attempted to tap into the video games market, working alongside Mindscape, the local distributor of Castlevania: Lords of Shadow 2, to create an event to help drive blood donations. At that event gamers were given the chance to get an early look at the new Castlevania in exchange for blood. I guess the problem GivBlod is having with young men is a global issue.
I recommend donating blood. You might not get a free copy of Bloodborne, but you will be doing something helpful, so why not!