The original meaning for Lolicon, derived from Lolita Complex. The Lolita Complex, is when someone who, over the age of consent, looks like a child. Many meanings for Lolicon have come about over many years.
The newer, more often used meaning for Lolicon, is a form of hentai.
Lolicon, is the sexual depiction of someone under the age of sixteen. You'll find older ages put into original hentai, since the age of consent for Japan, is fourteen.
The alternative spelling for Lolicon, is Rorikon.
"Last night, a few friends and I looked at some Lolicon."