1) One who frequents forums, chatrooms, or other online communities and doesn't take long to mention pointedly that he/she is a proud bisexual. The bisexual then relishes the attention from said community's more gullible and/or pathetic members. Internet Bisexuals are usually female, or males posing as females for attention.
2) By extension, anyone who lies about being bisexual or exaggerates sexual deviance for recognition or to fill a vacuum in personality.
"ZOMG where do you girls live? You should all throw on some schoolgirl outfits and come on down. We'll have ourselves a ball. ;-) <3 <3 ..."