He was best friends with my husband's dad, and with Remus Lupin and Sirius Black. They were all best friends, until the Potters went into hiding and Peter handed them over to the Dark Lord and got them killed.
Sirius went after him, and Peter killed 13 people faking his own death and framing Sirius for it.
Then, Peter lived as a pet rat with my family in my house for years, listening in on everything, watching everything. And then he brought back You-Know-Who again and started the war.