Some day, decades from now, this guy is going to retire... he'll probably be a bit too old and maybe a bit too plump to wear this anymore, and time moving on, as it does, few will understand its significance, so he'll pack it away in the attic.

Some time, hopefully many, many years later, he'll pass on, having lived a full life, leaving his estate, his fortune, and his belongings to his many children, nieces, and nephews. They'll politely divvy up the land, the money, Grandmother's antique silverware, etc. A few curious old boxes no one can identify will get sent to an eccentric nephew who lives in the country.... he'll store them away without opening them, forgetting the whole matter because, at the moment, he's more interested in studying newts or something.

One day, many further years on, the nephew's granddaughter, now an aged pensioner and philanthropist herself, will take it on herself to go through a few of the old family things, to see if anything might be donated to the local shelters. With a frail, wrinkled hand, she'll brush the dust off a few ancient-looking boxes she's never seen before, part of the family trust from way back. She'll carefully trim away the brittle and flaking packing tape with a pocket laser-trimmer... and, as she opens the worn and faded box, a ray of light from the setting sun will struggle through the suspended dust-motes to cast itself upon the contents. In that instant, she will look on the face of an ancient evil, too terrible to describe. The shock triggers a massive coronary heart attack and, after a few terrible moments, her noble and generous heart will seize and then cease to beat forever.

You killed her. Not just the cosplayer, but all of you. You should be ashamed. I hope you're proud of yourselves.