The people that log in at the Abyssal Demons when there's already 3 people there, and stay. Then their friend walks in, and his friend, and his friend, and before you know there's 7 or 8 people there, and none of them has the common descensy to hop worlds. Or when you both go for the same monster and the other guy gets it and says "Soz". It happens, you don't have to apologise every freakin time.