Katy Perry’s “Teenage Dream” co-star Josh Kloss says he has carried “silent trauma” with him since the pop star allegedly exposed his penis at a party without his consent nearly 14 years ago. In his first — and “last” — interview since making the claims publicly via Instagram in August 2019, Kloss exclusively told Page Six, “It’s hard to bring up something that seems irrelevant to a lot of people.” However, after actress Ruby Rose came forward with sexual assault allegations against Perry — claims the singer has vehemently denied — Kloss felt it was “important” to be “brave” and “show my face and explain myself.” “The world can judge me, you know?” he added. In an exclusive interview with Page Six, Katy Perry’s “Teenage Dream” co-star Josh Kloss (seen here) reflected on the time the pop star allegedly exposed his penis at a party without his consent. Page Six Kloss played Perry’s on-screen love interest in her music video for “Teenage Dream,” which was shot in July 2010.…