Okay, that one is rather long to explain.

You see, I have friend (well, now friends) that is very good at puns. But sometimes they're so terrible we say they just go commit suicide. From there came the idea of puns being lemmings. Due to a certain game and a certain documentary, there a common (a very false) knowledge that lemmings are suicidal. So, from now, when someone makes a very bad pun, we say he "do" or "kill" a lemming... and sometimes it's so bad a pun can kill a few at once. Then this pic...