Someone who decides, in the last minute, to get him/herself into a picture he/she wasn't invited to and sometimes ends up ruining a perfectly good picture.
-Liz "This picture of is so cute! Too bad David ruined it by jumping in the background with his drunk face!"
-Gabi "Yeah, he always does that! Even if we never take a picture of him, he'll always end up in the piture. What a picture creeper."