A young male person who likes to troll websites for younger boys preferably between the ages of 13 and 18. MrPeeps tend to also be full of themselves and like to waste money as to make their online persona more festive and geared toward attracting minors.
"Wow some weird old guy asked for my nudes last night"
"OMG, you've got a MrPeeps to deal with!"
"Dammit Tengaged Moderation unbanned WWEMrPeeps last night, this is worse than food poisoning on Christmas and your birthday combined."