Literally
by Jeff
Image text: The chemistry experiment had me figuratively -- and then shortly thereafter literally -- glued to my seat.
Let's see if we can tease this one out. The character with the hair that pops out of the side of the first frame is the character standing next to the girl in the 7th grade flashback. The one speaking in the first frame is the leftmost character in the right group.
The hairy character misuses the word "literally", and one of his classmates calls him out on it. The hairy character follows the classmate waiting to get him back for misusing "literally". However, it takes 18 years and the hairy character seemingly neglects his personal hygiene in the process.
Here's the rule of thumb: unless it actually happened, do not use "literally".

April 9th, 2010
the pun however lies in the fact, that the non-hairy mate actually did not use ‘literally’ wrong… =D Chemistry can literally glue you on your chair .)
December 29th, 2010
Did you see the 2nd joke? “You are literally the craziest person I’ve ever met” was actually used correctly, even though the hairy guy claims it isn’t. XD