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- Why did Scabbers stay at Hogwarts? 7 answers
As we were told, he only sought out his master because he had no choice. At least, Voldemort thinks so:
“And then, not even a year ago, when I had almost abandoned hope, it happened at last... a servant returned to me. Wormtail here, who had faked his own death to escape justice, was driven out of hiding by those he had once counted friends, and decided to return to his master." GoF, The Death Eaters
and he's probably right as Peter, once set on finding Voldemort found him in Albania (!) even before the new school term started.
So we have Peter living at Hogwarts / at the Weasleys why exactly? To gain information from Arthur, who was a ministry employee to do what...?
Wouldn't it be nicer running abroad or polyjuicing himself into someone else or even living as a muggle? Wouldn't it be better than sleep with Percy/Ron and eat leftovers?
What was exactly Peter's plan until he was caught by Sirius? To live his life as a rat?