What's Volta's favorite kind of thing to collect about her (universe respective) favorite hero?
Personal memorabilia. Things Arthur Simonds himself had a hand in making, or having made, or used himself. Equipment from the old days, or curios from his time as minister of defense in the war tower. One of her favorites is his old swordstick, from well after the leg injury that ended his career as True North II, disguised as a beloved wooden cane with a uniquely carved handle. She keeps it in pristine, freshly varnished condition after it very mysteriously found its way into her ever-expanding collection.
There are other favorites of course. True North II's old grappling gun (a gift from a loved one, stolen from a museum up north at her behest!), the first all-metal aluminum lunchbox with restored paint, and of course the reprint of the True North, True Stories issue she read for the first time at age five, a gift from her au pair, and the entire reason for her hyperfixation on TNII in the first place.
That one never leaves its protective sleeve anymore, the paper's too fragile from reading and re-reading.
Awww… That thief must love her very much to do something so reckless!