When two or more friends are too close for comfort. spending everyday and every night together. Often when one or two of the group are away for example on holiday the rest of the group begin to get suicidal withdrawal symptoms within the hour. Leads to very different behaviour such as inviting friends out that they haven't spoken to in a while seeing them as a "last resort"
Bumbuddy: "man i really miss those two do you?"
normal friend: "no it's been 45 minutes"
Bumbuddy: "oh my god i can't believe you just said that"
normal friend: "dude, you only miss bumming them"