Justin Bieber is already a big star, but he's being sued for trying to get even bigger -- by a man who claims The Bieb stole his credit card to buy penis enlargement pills.

According to TMZ, the Michigan man, who claims to be Selena Gomez's real father, has made a variety of insane accusations, including:

• Justin stealing money to pay for an abortion for Selena.
• Usher violating one of his private orifices with a lit firework while playing the Katy Perry song of the same name.
• Justin racking up credit card bills for penis enlargement pills and cocaine.