Purple Silkie (aka Passion) is a separated emotion of the Teen Titans' pet, Silkie. Along with the other clones of Silkie, he takes on Robin's Emoticlones. Purple Silkie's only appearance so far is in the Season 2 episode "Some of Their Parts".
At the beginning of the episode, Purple Silkie is temporarily separate from the other 4 Silkies when Silkie ate the Mysterious Prism. Starfire mentioned that she liked Purple Silkie the best, but Robin rejoined Purple Silkie with the others, however, preferring that people are better in their whole. After Robin divides himself into his five personalities, despite what he said before about people being better in their whole, the Ray Gun for the Prism is broken again. Silkie swallows it again and is divided. Starfire begs the Silkies to bring Robin back together. Purple Silkie takes out Brown Robin, the perfectionist side of Robin, by giving him a huge kiss with his oversized lips. After all 5 Robins are defeated, Purple Silkie is reunited with the other Silkies.
Purple Silkie's body is identical to the whole Silkie's, but he has eyelashes which makes him appear to be female, even though he is not. He has enlarged lips and half-lidded eyes. His antenna, stinger, and eyelids are a darker purple than the rest of his body.