Arcee

A seeming anomaly to the Transformers universe, Arcee first appeared in the 1986 cult classic The Transformers: The Movie as an Autobot living and working in Autobot City on Earth, circa 2005 in the Gen 1 series continuity. She first appears as a seeming romantic interest to Hot Rod, but that isn't necessarily the case, since the Transformers as a species don't have a true concept of gender as many species on Earth and many more aliens in other series do. Arcee's transformation converts her into a convertible automobile (akin to what Barbie dolls have).

The Generation one series (running stateside from 1984-1990) is the first series in which she is featured as a fully-fledged Autobot, she next appeared in the Japanese exclusive Headmasters series, and did not resurface again until 2004's Transformers Energon, next appearing in the 2008 series Transformers Animated as a recurring guest star, next she appeared in the 2009 live action film Transformers Revenge of the Fallen, and is currently one of the main characters in the series Transformers Prime, she is also the only character to appear in every episode of that series thus far. Her modern alt-mode is a motorcycle.