When a person and a fullsuit replica of them are both present in a scene.

Can be a fursuit, rubber suit, mascot suit, or any material & construction, so long as the suit is explicitly shown (or heavily implied) to be a believable disguise, an expert cosplay, or the like.

Familiar tropes include:

• anthros fursuiting as each other
• agreed-upon understudy or mascot
• evil genius's drone-esque clone army
• impersonating a rival love-interest
• forced impersonation via coercion or hypnosis
• super-spy kidnaps and impersonates a target
• getting caught by the person you're disguised as
• suit-enabled TF into a flesh-and-blood clone
• identity-play among friends or lovers
• kinky or BDSM flavours of any of the above

Does NOT include:

• costume of a known character that is NOT also present
• person transforming into an empty costume of themself
• generic dronification or "clone-suits"
• the Imposter(s) from Among Us