I've seen him in shirts and фото that have DSC what does it mean?

It's the Divide Social club, a Дизайн company run by Milo and a group of his friends.
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From what I can gather it stands for Divide Social Club and it's some kind of production company started by Milo and a group of his friends. Ты can find them on here dividesocialclub.tumblr.com/ as well as myspace and (I believe) twitter. Hope that helps.