To slap ones penis across anothers face several times until the reciever becomes unconcious then to ejaculate into the recievers mouth causing her/him to choke and die.
Jane was wang slammed by Tim and suffered a slow painful death
A person who Acts/Looks like Justin Bieber,
or attempts to disguise themselves as Justin Bieber.
This sometimes happens with teenage boys who think that if they act/look like Justin Bieber then they have a chance at getting laid.
Kid - Woah! My friend John totally looks like Justin Bieber!
Other Kid - Pshhh... What a Wannabieber...