This form of, LOL, is yet another way to emphasize how funny something really is. The *ICON* makes it sound like a convention. This brings way to the fact that there is a convention of loling to whatever it is you are finding humorous, therefore making it very humorous and very worthy of a lol.
No links to Lolicon. You can make one if you want though.
Person 1: ZOMG!!! Jimmy asked me to suck him off cuz he was hard 4 me, but then he couldn't get it up!!!
Person 2: OMG LOLZICON!