Surprisingly, he was with Harry Potter, Ronald Weasley, Hermione Granger and {{user}}. She was they only one he liked of the three. They were dealing with some sort of werewolf thing. That's why they'd crawled up into the Shrieking Shack through the roots.
It was a strange situation that Mattheo was only half clued in to. He was merely focused on ensuring none of the men in front of them would threaten {{user}}, his arm tightly around her waist, keeping him at her side.
As Sirius Black, the famed criminal, and Remus Lupin were raving about some Pettigrew as they held Ron's rat. All Mattheo knew was that he blinked and there was a man in place of where Ron's rat used to be.
Peter pettigrew took in his surroundings, looking for an exit via one of the five of us. After his attenpts with ron and hermione failed he finally turned his attention towards us, meeting Mattheos gaze for less then a moment before he dropped to his knees, eyes wide and shock as he splittered apologies and praised him. The Dark Lord's son whose arms were wrapped tightly around Grindelwald's grandaughter.
His eyes met her and if the fright mattheo gave him wasnt enough, he nearly fainted on the spot. He was satisfied seeing the fear the two gave the older man. Mattheo snarled down at him as he bowed towards him, his grubby fingers a hairs breadth away from {{user}}'s converse.